Teach "git remote" a mirror mode

When using the "--mirror" option to "git remote add", the refs will not
be stored in the refs/remotes/ namespace, but in the same location as
on the remote side.

This option probably only makes sense in a bare repository.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Documentation/git-remote.txt

@@ -10,7 +10,7 @@ SYNOPSIS
 --------
 [verse]
 'git-remote'
-'git-remote' add [-t <branch>] [-m <branch>] [-f] <name> <url>
+'git-remote' add [-t <branch>] [-m <branch>] [-f] [--mirror] <name> <url>
 'git-remote' show <name>
 'git-remote' prune <name>
 'git-remote' update [group]
@@ -45,6 +45,10 @@ multiple branches without grabbing all branches.
 With `-m <master>` option, `$GIT_DIR/remotes/<name>/HEAD` is set
 up to point at remote's `<master>` branch instead of whatever
 branch the `HEAD` at the remote repository actually points at.
++
+In mirror mode, enabled with `--mirror`, the refs will not be stored
+in the 'refs/remotes/' namespace, but in 'refs/heads/'.  This option
+only makes sense in bare repositories.
 
 'show'::
 

git-remote.perl

@@ -278,7 +278,9 @@ sub add_remote {
 
 	for (@$track) {
 		$git->command('config', '--add', "remote.$name.fetch",
-			      "+refs/heads/$_:refs/remotes/$name/$_");
+				$opts->{'mirror'} ?
+				"+refs/$_:refs/$_" :
+				"+refs/heads/$_:refs/remotes/$name/$_");
 	}
 	if ($opts->{'fetch'}) {
 		$git->command('fetch', $name);
@@ -409,6 +411,10 @@ elsif ($ARGV[0] eq 'add') {
 			shift @ARGV;
 			next;
 		}
+		if ($opt eq '--mirror') {
+			$opts{'mirror'} = 1;
+			next;
+		}
 		add_usage();
 	}
 	if (@ARGV != 3) {