We have a gitolite/check_fedmsg_hooks role, which installs a script and
schedules it.
Turns out, this script does more than just checking the fedmsg hooks,
depending on the command-line arguments used when running it.
As such, it makes sense to separate it out into its own role, and make
the gitolite/check_fedmsg_hooks role (and any other one using the
script) depend on it.
For example, this script is used for Fedora Hosted (still in Puppet),
and will soon be used for a new distgit hook check.
We already use the update hook for gitolite.
This introduces a new update hook, which merely chains the gitolite one,
and a new one to block pushes to badly named branches.
The new hook was written originally by Till Maas.
https://fedorahosted.org/rel-eng/ticket/4071
