Add a simple OpenGL ES 2.0 test program that displays a camera preview stream.

Uses a SurfaceTexture feeding into a OpenGL ES2 GLSurfaceView. Also
uses accelerometer data and SurfaceTexture-provided timestamps for a
simple physics simulation which moves the camera preview oval in
response to device movement.

Change-Id: I275a0c6a4e25829d617e635b25e70e2a9c8455cb