Merge master branch for tracking l10n updates of next release

Use master branch to track l10n updates for git next release, while
use maint branch to track l10n updates for git stable version.

1 files changed, 366 insertions, 0 deletions

diff --git a/contrib/subtree/git-subtree.txt b/contrib/subtree/git-subtree.txt
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+git-subtree(1)
+==============
+
+NAME
+----
+git-subtree - Merge subtrees together and split repository into subtrees
+
+
+SYNOPSIS
+--------
+[verse]
+'git subtree' add   -P <prefix> <commit>
+'git subtree' pull  -P <prefix> <repository> <refspec...>
+'git subtree' push  -P <prefix> <repository> <refspec...>
+'git subtree' merge -P <prefix> <commit>
+'git subtree' split -P <prefix> [OPTIONS] [<commit>]
+
+
+DESCRIPTION
+-----------
+Subtrees allow subprojects to be included within a subdirectory
+of the main project, optionally including the subproject's
+entire history.
+
+For example, you could include the source code for a library
+as a subdirectory of your application.
+
+Subtrees are not to be confused with submodules, which are meant for
+the same task. Unlike submodules, subtrees do not need any special
+constructions (like .gitmodule files or gitlinks) be present in
+your repository, and do not force end-users of your
+repository to do anything special or to understand how subtrees
+work. A subtree is just a subdirectory that can be
+committed to, branched, and merged along with your project in
+any way you want.
+
+They are also not to be confused with using the subtree merge
+strategy. The main difference is that, besides merging
+the other project as a subdirectory, you can also extract the
+entire history of a subdirectory from your project and make it
+into a standalone project. Unlike the subtree merge strategy
+you can alternate back and forth between these
+two operations. If the standalone library gets updated, you can
+automatically merge the changes into your project; if you
+update the library inside your project, you can "split" the
+changes back out again and merge them back into the library
+project.
+
+For example, if a library you made for one application ends up being
+useful elsewhere, you can extract its entire history and publish
+that as its own git repository, without accidentally
+intermingling the history of your application project.
+
+[TIP]
+In order to keep your commit messages clean, we recommend that
+people split their commits between the subtrees and the main
+project as much as possible.  That is, if you make a change that
+affects both the library and the main application, commit it in
+two pieces.  That way, when you split the library commits out
+later, their descriptions will still make sense.  But if this
+isn't important to you, it's not *necessary*.  git subtree will
+simply leave out the non-library-related parts of the commit
+when it splits it out into the subproject later.
+
+
+COMMANDS
+--------
+add::
+	Create the <prefix> subtree by importing its contents
+	from the given <refspec> or <repository> and remote <refspec>.
+	A new commit is created	automatically, joining the imported
+	project's history with your own.  With '--squash', imports
+	only a single commit from the subproject, rather than its
+	entire history.
+
+merge::
+	Merge recent changes up to <commit> into the <prefix>
+	subtree.  As with normal 'git merge', this doesn't
+	remove your own local changes; it just merges those
+	changes into the latest <commit>.  With '--squash',
+	creates only one commit that contains all the changes,
+	rather than merging in the entire history.
+
+	If you use '--squash', the merge direction doesn't
+	always have to be forward; you can use this command to
+	go back in time from v2.5 to v2.4, for example.  If your
+	merge introduces a conflict, you can resolve it in the
+	usual ways.
+	
+pull::
+	Exactly like 'merge', but parallels 'git pull' in that
+	it fetches the given commit from the specified remote
+	repository.
+	
+push::
+	Does a 'split' (see above) using the <prefix> supplied
+	and then does a 'git push' to push the result to the 
+	repository and refspec. This can be used to push your
+	subtree to different branches of the remote repository.
+
+split::
+	Extract a new, synthetic project history from the
+	history of the <prefix> subtree.  The new history
+	includes only the commits (including merges) that
+	affected <prefix>, and each of those commits now has the
+	contents of <prefix> at the root of the project instead
+	of in a subdirectory.  Thus, the newly created history
+	is suitable for export as a separate git repository.
+	
+	After splitting successfully, a single commit id is
+	printed to stdout.  This corresponds to the HEAD of the
+	newly created tree, which you can manipulate however you
+	want.
+	
+	Repeated splits of exactly the same history are
+	guaranteed to be identical (ie. to produce the same
+	commit ids).  Because of this, if you add new commits
+	and then re-split, the new commits will be attached as
+	commits on top of the history you generated last time,
+	so 'git merge' and friends will work as expected.
+	
+	Note that if you use '--squash' when you merge, you
+	should usually not just '--rejoin' when you split.
+
+
+OPTIONS
+-------
+-q::
+--quiet::
+	Suppress unnecessary output messages on stderr.
+
+-d::
+--debug::
+	Produce even more unnecessary output messages on stderr.
+
+-P <prefix>::
+--prefix=<prefix>::
+	Specify the path in the repository to the subtree you
+	want to manipulate.  This option is mandatory
+	for all commands.
+
+-m <message>::
+--message=<message>::
+	This option is only valid for add, merge and pull (unsure).
+	Specify <message> as the commit message for the merge commit.
+
+
+OPTIONS FOR add, merge, push, pull
+----------------------------------
+--squash::
+	This option is only valid for add, merge, push and pull
+	commands.
+
+	Instead of merging the entire history from the subtree
+	project, produce only a single commit that contains all
+	the differences you want to merge, and then merge that
+	new commit into your project.
+	
+	Using this option helps to reduce log clutter. People
+	rarely want to see every change that happened between
+	v1.0 and v1.1 of the library they're using, since none of the
+	interim versions were ever included in their application.
+	
+	Using '--squash' also helps avoid problems when the same
+	subproject is included multiple times in the same
+	project, or is removed and then re-added.  In such a
+	case, it doesn't make sense to combine the histories
+	anyway, since it's unclear which part of the history
+	belongs to which subtree.
+	
+	Furthermore, with '--squash', you can switch back and
+	forth between different versions of a subtree, rather
+	than strictly forward.  'git subtree merge --squash'
+	always adjusts the subtree to match the exactly
+	specified commit, even if getting to that commit would
+	require undoing some changes that were added earlier.
+	
+	Whether or not you use '--squash', changes made in your
+	local repository remain intact and can be later split
+	and send upstream to the subproject.
+
+
+OPTIONS FOR split
+-----------------
+--annotate=<annotation>::
+	This option is only valid for the split command.
+
+	When generating synthetic history, add <annotation> as a
+	prefix to each commit message.  Since we're creating new
+	commits with the same commit message, but possibly
+	different content, from the original commits, this can help
+	to differentiate them and avoid confusion.
+	
+	Whenever you split, you need to use the same
+	<annotation>, or else you don't have a guarantee that
+	the new re-created history will be identical to the old
+	one.  That will prevent merging from working correctly. 
+	git subtree tries to make it work anyway, particularly
+	if you use --rejoin, but it may not always be effective.
+
+-b <branch>::
+--branch=<branch>::
+	This option is only valid for the split command.
+
+	After generating the synthetic history, create a new
+	branch called <branch> that contains the new history. 
+	This is suitable for immediate pushing upstream. 
+	<branch> must not already exist.
+
+--ignore-joins::
+	This option is only valid for the split command.
+
+	If you use '--rejoin', git subtree attempts to optimize
+	its history reconstruction to generate only the new
+	commits since the last '--rejoin'.  '--ignore-join'
+	disables this behaviour, forcing it to regenerate the
+	entire history.  In a large project, this can take a
+	long time.
+
+--onto=<onto>::
+	This option is only valid for the split command.
+
+	If your subtree was originally imported using something
+	other than git subtree, its history may not match what
+	git subtree is expecting.  In that case, you can specify
+	the commit id <onto> that corresponds to the first
+	revision of the subproject's history that was imported
+	into your project, and git subtree will attempt to build
+	its history from there.
+	
+	If you used 'git subtree add', you should never need
+	this option.
+
+--rejoin::
+	This option is only valid for the split command.
+
+	After splitting, merge the newly created synthetic
+	history back into your main project.  That way, future
+	splits can search only the part of history that has
+	been added since the most recent --rejoin.
+	
+	If your split commits end up merged into the upstream
+	subproject, and then you want to get the latest upstream
+	version, this will allow git's merge algorithm to more
+	intelligently avoid conflicts (since it knows these
+	synthetic commits are already part of the upstream
+	repository).
+	
+	Unfortunately, using this option results in 'git log'
+	showing an extra copy of every new commit that was
+	created (the original, and the synthetic one).
+	
+	If you do all your merges with '--squash', don't use
+	'--rejoin' when you split, because you don't want the
+	subproject's history to be part of your project anyway.
+
+
+EXAMPLE 1. Add command
+----------------------
+Let's assume that you have a local repository that you would like
+to add an external vendor library to. In this case we will add the
+git-subtree repository as a subdirectory of your already existing
+git-extensions repository in ~/git-extensions/:
+
+	$ git subtree add --prefix=git-subtree --squash \
+		git://github.com/apenwarr/git-subtree.git master
+
+'master' needs to be a valid remote ref and can be a different branch
+name
+
+You can omit the --squash flag, but doing so will increase the number
+of commits that are incldued in your local repository.
+
+We now have a ~/git-extensions/git-subtree directory containing code
+from the master branch of git://github.com/apenwarr/git-subtree.git
+in our git-extensions repository.
+
+EXAMPLE 2. Extract a subtree using commit, merge and pull
+---------------------------------------------------------
+Let's use the repository for the git source code as an example.
+First, get your own copy of the git.git repository:
+
+	$ git clone git://git.kernel.org/pub/scm/git/git.git test-git
+	$ cd test-git
+
+gitweb (commit 1130ef3) was merged into git as of commit
+0a8f4f0, after which it was no longer maintained separately. 
+But imagine it had been maintained separately, and we wanted to
+extract git's changes to gitweb since that time, to share with
+the upstream.  You could do this:
+
+	$ git subtree split --prefix=gitweb --annotate='(split) ' \
+        	0a8f4f0^.. --onto=1130ef3 --rejoin \
+        	--branch gitweb-latest
+        $ gitk gitweb-latest
+        $ git push git@github.com:whatever/gitweb.git gitweb-latest:master
+        
+(We use '0a8f4f0^..' because that means "all the changes from
+0a8f4f0 to the current version, including 0a8f4f0 itself.")
+
+If gitweb had originally been merged using 'git subtree add' (or
+a previous split had already been done with --rejoin specified)
+then you can do all your splits without having to remember any
+weird commit ids:
+
+	$ git subtree split --prefix=gitweb --annotate='(split) ' --rejoin \
+		--branch gitweb-latest2
+
+And you can merge changes back in from the upstream project just
+as easily:
+
+	$ git subtree pull --prefix=gitweb \
+		git@github.com:whatever/gitweb.git master
+
+Or, using '--squash', you can actually rewind to an earlier
+version of gitweb:
+
+	$ git subtree merge --prefix=gitweb --squash gitweb-latest~10
+
+Then make some changes:
+
+	$ date >gitweb/myfile
+	$ git add gitweb/myfile
+	$ git commit -m 'created myfile'
+
+And fast forward again:
+
+	$ git subtree merge --prefix=gitweb --squash gitweb-latest
+
+And notice that your change is still intact:
+	
+	$ ls -l gitweb/myfile
+
+And you can split it out and look at your changes versus
+the standard gitweb:
+
+	git log gitweb-latest..$(git subtree split --prefix=gitweb)
+
+EXAMPLE 3. Extract a subtree using branch
+-----------------------------------------
+Suppose you have a source directory with many files and
+subdirectories, and you want to extract the lib directory to its own
+git project. Here's a short way to do it:
+
+First, make the new repository wherever you want:
+
+	$ <go to the new location>
+	$ git init --bare
+
+Back in your original directory:
+
+	$ git subtree split --prefix=lib --annotate="(split)" -b split
+
+Then push the new branch onto the new empty repository:
+
+	$ git push <new-repo> split:master
+
+
+AUTHOR
+------
+Written by Avery Pennarun <apenwarr@gmail.com>
+
+
+GIT
+---
+Part of the linkgit:git[1] suite