Fixed random crashes, added new settings

See Issues 5 and 11 for more details on random crashes, as well as [this reddit post](http://www.reddit.com/r/jailbreak/comments/2cq2hi/request_fix_priority_hub_cross_post_from/).

Added settings/features: 

* Privacy Mode: hides notifications when they first come in.
* Collapse on Lock: collapses notifications into their respective icons on lock
* Colorize Selected Background: colorizes selectedView based on the icon of the selected app

Misc:
* Broke headers out into a separate file
* Changed ivars in PHController.h/.m to properties because of dangling pointer described in Issue 11