Fixes to bugs I introduced when removing anchorBody and anchorTransform from RigidFrames.  Also, bug fixes in making comparisons in testFrames.  Specifically:

1. correct transposition when calculating a FixedFrame's transform.
2. removed vestigial references to getAnchorBody() and other "Anchor" based methods.
3. converted uses of c++ built in assert to our ASSERT when making comparisons in testFrames.  unlike assert, ASSERT will do comparisons in both release and debug builds.