Remove upload-tar and make git-tar-tree a thin wrapper to git-archive

The command now issues a big deprecation warning message and runs
git-archive command with appropriate arguments.

git-tar-tree $tree_ish $base always forces $base to be the leading
directory name, so the --prefix parameter passed internally to
git-archive is a slash appended to it, i.e. "--prefix=$base/".

Signed-off-by: Junio C Hamano <junkio@cox.net>

git.c

@@ -263,7 +263,6 @@ static void handle_internal_command(int argc, const char **argv, char **envp)
 		{ "update-index", cmd_update_index, RUN_SETUP },
 		{ "update-ref", cmd_update_ref, RUN_SETUP },
 		{ "upload-archive", cmd_upload_archive },
-		{ "upload-tar", cmd_upload_tar },
 		{ "version", cmd_version },
 		{ "whatchanged", cmd_whatchanged, RUN_SETUP | USE_PAGER },
 		{ "write-tree", cmd_write_tree, RUN_SETUP },