let's trigger alerts if the error message changes - not only if the state changes.
e.g. we're in 'warning' for a day, something else fails, and the monitoring script appends the other error to the message. This should trigger another email, and update pagerduty with the new message text.
actually, use an empty dict if we can't parse the json.
Merge pull request #6 from manos/warn-on-message-state

let's trigger alerts if the error message changes - not only if the stat...