* New media_player platform for Russound devices using the RIO protocol
Auto discovers zones and sources
Handles media metadata from sources that support it
asyncio implementation
Push updates for any zone or source changes so no polling required.
* Fixed up linting issues
* Addressing PR feedback
Updated russound_rio dependency to 0.1.3
Use enumerate_zones and enumerate_sources methods instead of doing it in
the platform.
Register callbacks in async_added_to_hass coroutine
Corrected behavior of async methods
Martin Donlon