Add a test for the tag lookup behaviour.
Add a test for the tag lookup behaviour.

Acidburn0zzz/rugged,tpickett66/rugged,libgit2/rugged,saraid/rugged,libgit2/rugged,saraid/rugged,Acidburn0zzz/rugged,tpickett66/rugged,libgit2/rugged,tpickett66/rugged,Acidburn0zzz/rugged,saraid/rugged