Support to show power state for LG Soundbars

The current LG Soundbar core integration does not show device’s power state. This makes it hard to create automation since the state is always shown as on. There is a PR released here by Chris that fixes this

I was hoping maybe @akinomeroglu or @mjg59 can merge python-temescal library and we can update the integration to support the power state for LG Soundbars.

Maybe we can also show the current state like playing, paused, etc as well?
Love you guys!