Distorted Android

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Make the 'Component Associations' UBO (on most devices) twice smaller -
use the 'packed' layout and 'ivec2' in place of 'ivec4'.

This forces us to dynamically probe the 'Stride' - number of 4-byte entities that the UBO's 'ivec4' takes - and correct the already-constructed UniformBlockAssociation objects in case this turns out to be different than the expected 2, i.e. tightly-packed....

Add a new API DistortedEffects.exists(long id)

Make per-component centers optional, controlled by API MeshBase.setUseCenters()

Bugfixes as a result of the Samsung Galaxy J4+ investigation:

1) By default, switch off transform feedback in the main program.
Create a new API 'needTransformFeedback()' to call if someone still needs TF in the main program.
2) lower the default max number of vertex effects to 30....

Progress with Megaminx.

Remove UBO from the fragment shader and come back to the default of only 5 concurrent fragment effects. All because UBOs in fragment shader crash on Adreno 510 and Adreno 506.

Minor.