Remove deprecated methods.

- Quaternion.isEmpty()
- Texture.dispose(GL)
- GLContext.getGLVersionMajor() / ..Minor()
- GLContextImpl.bindPbufferToTexture() / releasePbufferFromTexture()
- MouseEvent.getWheelRotation()
-
Use JoglVersion.getGLStrings(..) in 'famous' tests, removes redundancy .. Gears* RedSquare*