Distorted Android

Minor.

Major refactoring: convert the Matrix Effects to be independent of the resolution of the surface we render to.

Re-write the first 15 apps to work with this.

Minor

Bugfix: create the Postprocessing buffer immediately.

1) bugfix computing Gaussian BLUR kernel (for odd radii, the last offset was incorrectly computed)
2) introduce more advanced method of detecting BLUR halo (compute depths in a new way)

Roll back the recent MIPMAP work.

Preliminary support for MIPMAP levels of the postprocessing buffers. (doesn't work yet)

Node: Sort children IDs when generating their list for the Map of (List<Children IDs>,NodeData).
This makes two internal nodes with the same children always isomorphic, no matter what is their order.

Release all TREE FBOs in Distorted.onPause().

Major:

1) in the Library, fix the fact that some applications (those that were creating their DistortedSurface objects outside of onSurfaceCreated or onSurfaceChanged) would not render after the activity went to background (press POWER to see that).
2) in the Apps, call the new 'Distorted.onPause()' API to fix the above problem...