Base: Floating window with multitasking

(cherry-picked ps 25 from omni gerrit)

basic floating window are taken from AOSPA (HALO) by @D4rKn3sSyS

Drawables courtesy of @Alex Cruz thanks to him :)

with heavy change to get this work for multitasking

this feature, has ability to:
1. Moveable window to various position
2. Scaling window with 2 finger like zoom in/out
3. Double tap in actionbar or above window to fullscreen or back to floating window
4. Automatically resize when Snapping into one of side (Top, Bottom, Left, Right)
   (taken from xhalofloatingwindow by @zst123)
5. Automatically switch focus from other app (taken from multiwindow by @xplodwild)
6. Unlimited floating window app (depends on RAM)

this is still under testing, to make fully works
so if there any bug because of this, DO NOT REPORT INTO OMNIROM JIRA

to make app launch using Floating window feature

you must add Intent.FLAG_FLOATING_WINDOW
before start an activity

for example you can look at https://gerrit.omnirom.org/6515

need https://gerrit.omnirom.org/#/c/6561

PS.17 : fix scaling
PS.18 : fix layout calculation when rotate
PS.19 : support minimize/maximize window (see App circle sidebar)
PS.20 : fix previouse app
PS.21 : rebased due to changes in 4.4.3_r1.1

Change-Id: Iad00c239de7d66e8bb45205ce626d4f08417b7cd

Conflicts:
	core/java/android/app/IActivityManager.java
	core/java/android/content/Intent.java
[1/2] Base: implement App circle sidebar

add whitelist app to include into circle view
rebased
make standalone patch

PS.15 : rebased
PS.16 : cleanup
PS.18 : build error fix

Change-Id: I08d2a3a7e0f8df20e801e585d4cac8547a740a3e

Conflicts:
	packages/SystemUI/res/values/custom_strings.xml
Base: App Circle sidebar (add support floating window)

PS.8 : rebased
PS.9 : add support minimize/maximize window
PS10 : rebased

Change-Id: Ied388a0a4054dfaf1d3e6fcdc33dd5aab28565a9

Conflicts:
	packages/SystemUI/res/values/custom_strings.xml
Base: App Circle sidebar (add support Samsung multiwindow flags)

this will automatically add app into app circle sidebar
if apps support samsung multiwindow flags
in their manifest

PS.2 : rebased

Change-Id: Ifa8965f1fb5d24987aed7d6d52a4e77deb48c455