This adds an app to get the RGBC values from the APDS9960 sensor,
and drives one APA102C with those values. The app works on the ARC
side of Arduino 101.
Change-Id: Iaee7bd11c06b03cf3c69f8ccb84cdb649634bb6c
Signed-off-by: Daniel Leung <daniel.leung@intel.com>