Reference iteration, take 3

Hopefully correct this time:
- iterating with globs assumes the glob is a full name, e.g. 'refs/heads/test-*' or 'H*'
- iterating without a glob uses a default glob of 'refs/*'

Author: charypar

redis/hiredis.c

@@ -342,7 +342,7 @@ int hiredis_refdb_backend__iterator(git_reference_iterator **_iter, struct git_r
 
 	backend = (hiredis_refdb_backend *) _backend;
 
-	reply = redisCommand(backend->db, "KEYS %s:%s:refdb:%s", backend->prefix, backend->repo_path, (glob != NULL ? glob : "*"));
+	reply = redisCommand(backend->db, "KEYS %s:%s:refdb:%s", backend->prefix, backend->repo_path, (glob != NULL ? glob : "refs/*"));
 	if(reply->type != REDIS_REPLY_ARRAY) {
 		freeReplyObject(reply);
 		giterr_set_str(GITERR_REFERENCE, "Redis refdb storage error");