simplified Type_Infer: eliminated separate datatypes pretyp/preterm -- only assign is_paramT TVars;
simplified Type_Infer: eliminated separate datatypes pretyp/preterm -- only assign is_paramT TVars;

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