jobrunner: puppetize HAT runner

The HAT jobrunner will spawn jobs by polling the fastcgi hhvm daemon via
curl spawned by the jobrunner loop. In detail:

* added a virtual host and the corresponding port definition
* added the apache modules needed
* disabled jit from command-line hhvm config

Change-Id: I3d002968c30827b2e8c0fdf6fc55d8846080a104
Signed-off-by: Giuseppe Lavagetto <glavagetto@wikimedia.org>