Adapt more accurately to different states in monit

Although we probably never experienced false alarms, I was pointed to this problem by [this post](http://lists.nongnu.org/archive/html/monit-general/2012-07/msg00022.html)

Studying monit's source (e.g. https://bitbucket.org/tildeslash/monit/src/d60968cf7972cc902e5b6e2961d44456e1d9b736/src/monit.h?at=master#cl-135) and the way, status is returned and handled by the [monit gem](https://rubygems.org/gems/monit) I came to the conclusion that we only need to alert (ie `data['All_Services_ok']` to false) for STATE_FAILED (1) and MONITOR_NOT (0x0)