One more time with the missing fields

Rachio implemented rate-limiting which caused the plugin to fail. We've addressed that and added several new events to help users identify when there are communication issues. Also added plugin checking against the plugin store.

They also changed the API, so until and if they ever add 'elevation', 'timeZone', 'paused' and 'utcOffset' back to the API we'll catch them. For now we set the value of those fields to 'unavailable from API'.