Merge branch 'jc/alternate-push'

* jc/alternate-push:
  push: receiver end advertises refs from alternate repositories
  push: prepare sender to receive extended ref information from the receiver
  receive-pack: make it a builtin
  is_directory(): a generic helper function

git.c

@@ -330,6 +330,7 @@ static void handle_internal_command(int argc, const char **argv)
 		{ "prune-packed", cmd_prune_packed, RUN_SETUP },
 		{ "push", cmd_push, RUN_SETUP },
 		{ "read-tree", cmd_read_tree, RUN_SETUP },
+		{ "receive-pack", cmd_receive_pack },
 		{ "reflog", cmd_reflog, RUN_SETUP },
 		{ "remote", cmd_remote, RUN_SETUP },
 		{ "repo-config", cmd_config },