General cleanup of commented out code in beam.cpp

git-svn-id: svn://svn.icculus.org/fs2open/trunk/fs2_open@10165 387891d4-d844-0410-90c0-e4c51a9137d3
General clean up of commented out #ifndef NDEBUG blocks

git-svn-id: svn://svn.icculus.org/fs2open/trunk/fs2_open@10166 387891d4-d844-0410-90c0-e4c51a9137d3