Player UI considerations

[galenriley]

Current version doesn't crash any more, but it's a wonky pattern.

At minimum, need to implement a PlayerView component and SinglePlayer screen to match Song pattern

But also, the whole Roster/Player/Song or Roster/TwitterList interaction is weird and the backbutton behavior is not sensible, so let's think about the whole thing.

[galenriley]

but like also the whole thing needs to be revisited, what with player image galleries and so on

[galenriley]

oh hey also there's a buncha calls like
this.props.navigation.setOptions({ header: null });
all over the place that don't cause harm to exist but do nothing (because the behavior we want is set in the navigator setup currently, and the way to do it in the screen is different) so delete all of those when addressing this ticket