GearVRf 2.3 and new prebuilt binary

The binary snapshot was created from the current version of GearVRf codes and tested with oculus v1.0.0.
See the wiki page for the build instructions: http://wiki.gearvrf.org/bin/view/GearVRfDeveloperGuide/GearVRfDevGuide200Start#BuildInstruct
For template samples for Android Studio and Eclipse, please refer to this posting: https://github.com/Samsung/GearVRf/releases/tag/2.2.1