Quick Settings: Swipe to switch

Adds the ability to switch to/from Quick Settings, using a sideways
swipe gesture.
Video demonstration: http://www.youtube.com/watch?v=jZaDVBIFAuA
(Video for the initial Patch Set only)

PatchSet2 : Fixed a line
PatchSet3 : Removed unnecessary line of coding
Path-set 4: Fixed build errors

Change-Id: Ice46cb0806c965cc9f9fa9f3355b317d42e83896