Fixes#104
@status filter was added to the master branch to support new status key from Alertmanager >=0.6.1
status ended up being nested in Alertmanager (it was added to solve AM issue 609 and that was a long PR with lots of changes), current unsee implementation ended being slightly off with how Alertmanager is naming this, it should actually be @state rather than @status.
Now that Alertmanager provides status=(unprocessed|suppressed|active) in the API it doesn't make sense to keep having separate filters for each value, merge @silenced & @inhibited into a single filter, update docs and UI
