These hooks are done for notifying Integrity instance of new Gerrit change update.
At the moment only patchset-created has been implemented, but creating new hooks is pretty easy; just copy the file and alter the arguments.
List of available hooks along with their params can be found from Gerrit’s manual: http://gerrit-documentation.googlecode.com/svn/Documentation/2.5/config-hooks.html
Information of what Integrity is can be found from here: http://integrity.github.com/
This assumes that hooks resides in default location, and that hooks dir hasn’t been already created
cd [your git clone dir]
git clone git@github.com:Smarre/gerrit-hooks.git
cd [gerrit root dir]
mkdir hooks
cd hooks
ln -s [git clone dir]/gerrit-hooks/[hook name].rb [hook-name]
cd -
sh bin/gerrit.sh restart
If you create new hook, please contribute it back! :)