goprotobuf: update weekly tag.

weekly tag now weekly.2011-04-13

R=bradfitzgo
CC=golang-dev
http://codereview.appspot.com/4437056

.hgtags

@@ -1,4 +1,5 @@
 f3ef978cda6fabc10f6039aeed960340547c6d5a release.r56
 f3ef978cda6fabc10f6039aeed960340547c6d5a release
 96dad172ec5b1aa6946f13f9cbf9cfe0fec40f05 weekly.2011-04-04
-96dad172ec5b1aa6946f13f9cbf9cfe0fec40f05 weekly
+37b09d1346b72c73a76672aa9a830bff9e6be014 weekly.2011-04-13
+37b09d1346b72c73a76672aa9a830bff9e6be014 weekly