While investigating a warning I noticed that a couple methods were
marked '// Not implemented', yet were, in fact, implemented.  The
implementations were empty && very obviously wrong.

I made the methods actually unimplemented, so a haphazard use
would fail to link instead of give the wrong runtime behavior.

git-svn-id: http://visit.ilight.com/svn/visit/trunk/src@6996 18c085ea-50e0-402c-830e-de6fd14e8384