push: --follow-tags

The new option "--follow-tags" tells "git push" to push annotated
tags that are missing from the other side and that can be reached by
the history that is otherwise pushed out.

For example, if you are using the "simple", "current", or "upstream"
push, you would ordinarily push the history leading to the commit at
your current HEAD and nothing else.  With this option, you would
also push all annotated tags that can be reached from that commit to
the other side.

Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/push.c

@@ -399,6 +399,8 @@ int cmd_push(int argc, const char **argv, const char *prefix)
 		OPT_BOOL(0, "progress", &progress, N_("force progress reporting")),
 		OPT_BIT(0, "prune", &flags, N_("prune locally removed refs"),
 			TRANSPORT_PUSH_PRUNE),
+		OPT_BIT(0, "follow-tags", &flags, N_("push missing but relevant tags"),
+			TRANSPORT_PUSH_FOLLOW_TAGS),
 		OPT_END()
 	};