Allow creating annotated tags

When creating annotated tags (by passing a message into them), you can use "git describe".
http://stackoverflow.com/questions/6693209/is-there-an-equivalent-to-gits-describe-function-for-mercurial says it is ``hg log -r . --template '{latesttag}-{latesttagdistance}-{node|short}\n'``.

However, ``hg log`` seems to also print the message of the tag commit.