Porting over the changes found by Nathan script for Disproportionation
family

1) Made XH_rad more general
Extending groups in Intra_R_Add_Exocyclic to match RMG-Py

Added Cdd to the terminal groups
Fix child relationships in R_Addition_Csm

Making the changes equivalent to commit

99b300c0afff5d9ed008dd5e06dce3c91758012d
Minor fixes to intra_H_migration family

In R3H_SS_S replacing R to R!H

Commit 423e70967803963f4b339c8899200b04a969c153
Minor corrections to in 1,2 Insertion family
A few children errors:

-Changed C to Cs in Cs_H and all its (numerous) descendants
-Changed C to Cd in Cd_H and all its descedents

fcdfa7c11e0ecf759acaee37e7604bab58d559dd
Debugging R_Add_Multibond by Naths script.
- 2 Ct ligands were wrongly named Cd
- redefined SJ (in older version Level 1 and Level 2 were identical)
Adding forbidden group to Intra_Diels_alder family

SOme of the rings with 3 conjugated double bonds undergo
intra diels alder to form highly strained rings. This
fix only solves one such case will possibly require hard coding
to eliminate all cases occuring under pyrolysis.