SemiRfc

TODO: define current SEM-I specs

Proposal based on discussion at the Abbey on 2013-08-28

Woodley argues that the SEM-I should have the hierarchy of gpreds. This will allow a tool to calculate MRS subsumption with only the SEM-I and the MRSs (i.e. without having to parse the grammar). E.g. currently we have:

def_q_rel : ARG0 x, BODY h, RSTR h.

And we'd like something like:

def_q_rel (def_udef_a_q_rel) : ARG0 x, BODY h, RSTR h.