Statusbar behaviour: Refactor everything (2/2)

Huge credit to @Bajee11 as I used his previous commits as examples for these. And of course credit
goes to @SlimRoms for their Status bar Auto-Hide and Quick Peek features!

-Switch to list preference versus checkboxes
-Give user 3 options (Show, Hide, and Auto hide statusbar)

Change-Id: I3bf3e9c9d38d98ca4596e767a765f0de7a537432