Move refspec pattern matching to match_refs().

This means that send-pack and http-push will support pattern refspecs,
so builtin-push.c doesn't have to expand them, and also git push can
just turn --tags into "refs/tags/*", further simplifying
builtin-push.c

check_ref_format() gets a third "conditionally okay" result for
something that's valid as a pattern but not as a particular ref.

Signed-off-by: Daniel Barkalow <barkalow@iabervon.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>

send-pack.c

@@ -354,6 +354,7 @@ static void verify_remote_names(int nr_heads, char **heads)
 		case -2: /* ok but a single level -- that is fine for
 			  * a match pattern.
 			  */
+		case -3: /* ok but ends with a pattern-match character */
 			continue;
 		}
 		die("remote part of refspec is not a valid name in %s",