grafx - Extensible Java Graphics Package Code

In BlockGenerator, adding 'originOccupied' leaf-level subordering for
findBestBlock().

Changing location of where lowestDepth is defined and used, in findBestBlock().
This is paving way for additional change which will break things. I want to
separate this change from the one which will break things.

Adding TODO comment above getCenterOfMass(), which further explains the problem
that we are dealing with.

Adding long comment to the top of findBestBlock(), which is private. The
purpose of this commit is to advertise my intention. I will be needing help.

Putting BlockMirrorImageCheck to a somewhat finalized state. We have a lot of
work to do. The idea of "canonical" totally disregarded reflections. We need
to fix that.

Uh oh. We have a problem, Houston. BlockMirrorImageCheck has discovered an
anomaly.

In BlockGenerator, adding getMirrorBlockZ(). Untested.

In BlockGenerator, adding equalsModuloOrientation(). Untested.

Using what seems to be the correct curve for UniformScale3D, during inversion.

Fixing the sqrt() of negative number issue. D'oh! Lol. All of this is so
related.