* Add suggested_area to MQTT Discovery
This adds suggested_area to MQTT discovery, so that the discovered devices could be automatically added to the proper area.
* Add abbreviation for MQTT suggested_area
* Remove extra whitespace
* Remove extra whitespace #2
* Added tests for MQTT Dicovery of suggested_area
* Fix test for MQTT suggested_area
* Better tests of MQTT suggested_area
Changes made as per feedback from @emontnemery