Add "shuffle playback" button to the Player when music is loaded

[mitchdowney]

This should be pretty easy to just randomize the tracks in the playerSyncQueueWithPlayer helper function, before setting them before and after the currently playing item. We have to make sure playerSyncQueueWithPlayer does not get called extra times though (only when you press play on a new item in the player).

[mitchdowney]

I think this could be a good first issue for a React Native contributor. The scope of changes might just be limited to the playerSyncQueueWithPlayer screen, the PlayerControls component, and use some AsyncStorage...and some global state updates so we can change the new shuffle button's state. Each of those steps I think might be simple, but there are a few different things involved.

[lovegaoshi]

i'm not sure why shuffle as a playmode natively was not done within RNTP; if i remember correctly ios is supported but api not exposed, and android is doable natively but not implemented, but there were talks to put it in. i used to use a purely js shuffle, which worked for me for <300 ish tracks in queue until I abandoned RNTP queue management all together.