Revamp default thumbnail

Conflicts:
	packages/SystemUI/src/com/android/systemui/recent/Recents.java
AOSB RecentApp : Add HTC Reflection Effect

PS1: support multi resolutions , hdpi, xhdpi , hdpi

PS2: generte small thumbnail to save memory in low resolutions

PS3: disable reflection effect if enable custon recent (slim)

thanks for Marc Landis from AOKP for the idea from 2 years
i just saw it when it suggested by liquid0624 my friend!

Stack help too :
http://stackoverflow.com/questions/22111468/thumbnail-reflection-with-drawable-instead-of-bitmap

Signed-off-by: hany <hany.alsamman@gmail.com>

Conflicts:
	packages/SystemUI/src/com/android/systemui/recent/RecentsPanelView.java