fix memo compilation, implement several hint opcodes
fix memo compilation, implement several hint opcodes

urbit/urbit,jfranklin9000/urbit,jfranklin9000/urbit,urbit/urbit,urbit/urbit,jfranklin9000/urbit,jfranklin9000/urbit,ngzax/urbit,ngzax/urbit,ngzax/urbit,ngzax/urbit,jfranklin9000/urbit,urbit/urbit,jfranklin9000/urbit,jfranklin9000/urbit,urbit/urbit,ngzax/urbit,urbit/urbit,ngzax/urbit,ngzax/urbit,urbit/urbit