tuned/modernized subst: Same.operation; renamed typ_subst_TVars to subst_type; renamed subst_TVars to subst_term_types; renamed subst_vars to subst_term; removed unused subst_Vars (covered by subst_term);
tuned/modernized subst: Same.operation;
renamed typ_subst_TVars to subst_type;
renamed subst_TVars to subst_term_types;
renamed subst_vars to subst_term;
removed unused subst_Vars (covered by subst_term);

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