added read_def_cterms, read_cterm (from thm.ML);
added read_def_cterms, read_cterm (from thm.ML);

MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle