* upgrade to aiopylgtv 0.3.0 and corresponding simplification and cleanup of webostv state tracking
* properly handle case where Live TV is not reported in list of apps
* fix tests (entity state is no longer linked to source id)
* fix pylint checks
* avoid unnecessary retrieval of channel list
* use only standard home assistant states
* migrate webostv to new aiopylgtv version of the library and add support
for generic commands, input/button commands, and callback state updates
* update requirements
* cleanup and bump aiopylgtv version
* update webostv unit tests
* make webostv unit tests work with python 3.7
* cleanup for code checks
* cleanup and code review
* make all client request functions coroutines
* make host required for webostv configuration
* remove generic command and button functionality plus related cleanup
* fix previous track function
* update unit tests
* fix imports for unit tests
* update unit test
* further unit test updates
* remove unnecessary setup call in unit tests
* restore previous behaviour with client key config file in hass configuration directory