Added alarm-notifier and alarm-evaluator services

This patch add the two services to the current puppet module to
be in line with the h1 release.

This change also comply with what Eoghan said in his comment, so
I removed the require of ceilometer::db class since the alarm is
not related with it.

It's also been removed the subscribe from evaluator.pp and from
notifier.pp since those two modules does not use the db.

This patch also give all the changes mgagne suggested.

Change-Id: Idfd422078d73aaee6da28cef35d825dd24e8afb8