Ignore silenced

[audunsolemdal]

Hard to test without generating mock data

note that the Docker image for this branch: aware-api/silencedtest1 is currently running on sensu-dashboard.

[soofstad]

Nice job.
But I don't think it should be necessary to fetch silenced events.
In the big list of all events, we could check if the event is silenced, and filter on that. Would require one less envvar aswell.
If we want to ignore them completely, or just not have them effect background color can be discussed.