Distorted Android

Add correct normal vectors to the PINCH effect. The effect is now fully 3D.

Make the 'PINCH' effect fully 3D (define its acting line in terms of (latitude,longitude) angle pair).

Still, something is not fully working in the Earth app with the effect - investigate.

Add (simplified, approximated) shading to the Sink effect, i.e. move the normal vectors.

Remove unused imports.

Finish the Rubik app.

Refactor the 'Generic' app.

Avoid a potential crash on exit

Before we start rendering, effects can always be added.

Bugfix: default, MAX region cannot be of Float.MAX_VALUE radius - then in the shader we can have an overflow. Make it 1000000 in radius.

1) new 'Rubik' app (skeleton)
2) MeshCubes: add support for custom texture mappings on each side (Rubik needs that!)