PlugInLeapNotice prefab is broken

[jo3w4rd]

3 things:

1. On the LeapC side, IsServiceConnected isn't working because of a bug in LeapC. This has been fixed in platform. -- the fix should be in the assets by now.
2. I am getting null object errors when the prefab is in the scene, so it seems that something might be missing from the prefab? -- further investigation reveals that at some point, some code was changed to expect a UI.Image instead of GUITexture, but other scripts still expect GUITexture.
3. We shouldn't need to check for a connection every frame. Probably a coroutine that runs every couple of seconds is more efficient.

[jo3w4rd]

Fixed in #490 (which removes the prefab, but adds a simpler setup with one class and one sprite texture)