Distorted Android

Move the defualt state of an Object to be in the center of the screen (rather than the bottom-left like before)

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

Some improvements to the Wind app - still does not look very realistic though :(

Correct Distort.

Make Distort truly 3D.

Fixes for some stuff discovered while making the Distort effect fully 3D:

- make MeshSphere's normal lengths be 1 (used to be 0.5)
- make the Effect3D app display precise values of the Center and Region vars.

Relax requirements on when we can call DistortedEffects.setMax().

Before this change one had to call it before creation of shaders and before any of the DistortedEffects classes got created.
This commit removes the second requirement so now with setMax it's just like with enabling effects: it's best done in onSurfaceCreated.

Massive: make the coordinate system agree with that of OpenGL (i.e. invert the Y axis).

Make the Sink effect fully 3D.

Correct the z-axis of the center of fragment effects (it was inverted)