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.
update and merge from master
small cleanups to FixedFrame.cpp.  Added a comment to clarify the math computing the transform on the mobilized body.  Also, converted tabs to spaces in this file to fix alignment issues.
Fix minor typo in comment.
Removed "+" typo and fixed comparison statement in FixedFrame implementation.
Merge pull request #226 from opensim-org/testFrames_remove_anchorBody

Test frames remove anchor body