Arcyd: fix branch url in reviews

Pass the branch name string instead of the branch object in abdt_git.

Add review-url-format and branch-url-format to the happy path
smoketests.

Format the 'abdcmnt_commenter.createdRevision' comments to be a bit
clearer and neater.

Test Plan:
$ ./precommit.sh
manually inspect review pages created from smoketests