Camera2: Smart scene icons w. original artwork

These are functional replacements for the smart scene indicators
created from scratch for CM, and fully owned by the project.

I'm sure the size, border weight may need some adjustment, but
they're currently identical to the burst mode indicators in:
http://review.cyanogenmod.org/#/c/55716/

Change-Id: Ia9e18aa2cd1f78b8ef3674e71cb151e522f2e139
Camera2: Fix burst mode, auto scene detect layout

* Prevent icons from stacking ontop of each other

Change-Id: I4a1c8ae360c7272bfa2833aaf64410a2778a7ff7
camera: Add metadata-based ASD

 * New cameras use the metadata callback to report the
   detected scene mode. Add support for this.
 * The asdModes array must be set for this to work, which
   should contain the ordered list of possible scenes,
   corresponding to the camera_asd_values array.

Change-Id: I07279ae30a4cbedef02bec702252eb7e2abacd4a
camera: Histogram, ZSL burst mode, HDR-on-ZSL

 * Optional features available on newer sensors
 * Histogram needs to be made pretty

Change-Id: Ic46c1dfcc1de32acc22928a4431d3601b03ef513