* Add support for Danfoss Air HRV systems.
* Correct lint errors after initial commit of Danfoss Air HRV support.
* A couple of lint fixes for danfoss_air.
* Refactor to comply with HA standards.
* Style fix.
* Use wildcard for danfoss_air in .coveragerc.
* Remove config example from header documentation.
Correct import name for platforms.