Term issue: general class for modified proteins

A general class indicating a protein has a "modified amino acid residue" (PR:000025513). Needs:
1) To be distinct from cleaved proteins
2) Would need to account for both has_part modified amino acid and has_component modified amino acid (NOTE: the former is parent for the latter, so only that needs to be accounted for; however, we need to check if that subclass relation is carried over to PRO)