New navring icons for power menu and last app. Let's follow CM changes

Change-Id: I9a012061faa03879c6769cd5a202acc9d7d1f28b

Conflicts:
	core/res/res/drawable-mdpi/ic_navigation_ring_lastapp_activated.png
	core/res/res/drawable-mdpi/ic_navigation_ring_lastapp_normal.png
	core/res/res/drawable-xxhdpi/ic_navigation_ring_lastapp_activated.png
	core/res/res/drawable-xxhdpi/ic_navigation_ring_lastapp_normal.png
Themes: Style, boot animation, and wallpaper previews

Change-Id: I2b367bf5336c03f2a4972a05b68922065cd4a701