Fixes to thermo radical groups so that they obey parent-child relationships.

Most changes were related to parents being Cs or Cd atomtypes but children
being more broad C atomtype.

2 real fixes:
-CO was previously not found to be a child of Radical parent.  Now it is
assigned as a child of RJ2_singlet.
-CdJ2-Sd_singlet was incorrectly assigned as L5 group rather than L4.