"Clear all" button on recent apps

Port forward from cm-10.2

Change-Id: I39c41ddd136118d481853b6ade33652f1358ce48

Force clear cache on 'clear all'

Add long click to 'clear all' button in recents panel to force
clear caches, dentries and inodes

Change-Id: Iaa0ff526707be5b21bf746767f6241f4f0b6c39e

Koush broke my cache!!!

Change-Id: Ia5796146de1b876772ea1ca487f43d3e933862da

Changelog:

PS 3-5:
* added support to change its position to any of the 4 corners or turn it off
(original author: benjamingoodwin)
* defaults to bottom_right

PS 6:
* Code cleanup
PS 7:
* no need for clearAllButton to be an instance variable
PS 8:
* universe boolean for triggering noApps

Change-Id: I9ebcf22f85957f61caefb14e0efd4cf2978d92cd