Use original data for the number and name of ordinal levels (if available)
Use original data for the number and name of ordinal levels (if available)

This also fixes a bug because, previously, the level names could have
been taken from the threshold matrix rownames. However, there are always
one fewer rownames than levels.

jpritikin/OpenMx,mhunter1/OpenMx,jpritikin/OpenMx,jpritikin/OpenMx,mhunter1/OpenMx,mhunter1/OpenMx,mhunter1/OpenMx,jpritikin/OpenMx,mhunter1/OpenMx,mhunter1/OpenMx,jpritikin/OpenMx,jpritikin/OpenMx