Smart Shuffle API Toggle

[zombiekiller567]

It's great that we have Web API support for seeing if 'smart_shuffle' is enabled through Get Playback State (even though documentation is out of date and doesn't actually show it as a field that's returned). However, we should be able to turn on and off smart shuffle in the same way we can turn on and off normal shuffle through Toggle Playback Shuffle 

An additional 'smart_shuffle_state=bool' parm in the endpoint would be great. 

It's also rather strange that even if you turn off shuffle through the "Toggle Playback Shuffle" endpoint that if smart shuffle is still enabled no actual change is made. Would be nice if toggling shuffle off at the very least disabled smart_shuffle as well.

[DiegoCJ]

Como on Spotify, add this feature already!!!