[1/2] base: omniswitch as default recents

OmniSwitch provides broadcast events for showing
and hiding the overlay

We need to make sure that OmniSwitch service is really
running else we will get no recents at all. Also on startup
it will take some time until the OmnISwitch service
has been started.

OmniSwitch will send a service start and stop broadcast
that will guard the usage of OmnSwitch

Change-Id: I5197060326c4997dc63c44339407dd2c52e59ab6

Conflicts:
	core/java/android/provider/Settings.java
	packages/SystemUI/src/com/android/systemui/statusbar/BaseStatusBar.java
[1/2] added Slim Recents as option

take reference add OmniSwitch as defaul recents by @Maxwen (Omnirom)

- make slim Recents as option between Aosp/OmniSwitch
- add a warning dialog when selecting

PS3: Rebase
PS4: Fix Settings.java derp
PS5: Set to private boolean as suggested by Tianrui
PS6: Rebase
PS7: Rebase
PS8: fix derp
PS9: Rebase && derp in a statement in BaseStatusBar.java
PS10: Another derp
PS11: Remove unneeded import from rebase
PS12: Derp fix
PS13: Another derp fix
PS14: Derp-o-rama
PS15: Rebase
PS16: Again another derp
PS17: rebase
PS18: fixed

Change-Id: I9d43f2e5a29ec9c29d172915a14a101907b93ac5

Conflicts:
	core/java/android/provider/Settings.java
	packages/SystemUI/AndroidManifest.xml
	packages/SystemUI/src/com/android/systemui/statusbar/BaseStatusBar.java