lwt: more removal of syntax extensions
lwt: more removal of syntax extensions

djs55/mirage-skeleton,Drup/mirage-skeleton,mor1/mirage-skeleton,samoht/mirage-skeleton,mor1/mirage-skeleton,Drup/mirage-skeleton,djs55/mirage-skeleton,samoht/mirage-skeleton,mirage/mirage-skeleton,mirage/mirage-skeleton