fix build with OCaml 5
there are several things:
- caml_ prefix for ocaml runtime C api, mechanical replace
- Pervasives gone, mechanical s/Pervasives/Stdlib/ (it raises minimum required OCaml version to 4.07)
- s/String.lowercase/String.lowercase_ascii/ etc (ocaml >= 4.03)
- caml/unixsupport.h now provides defines that were previously vendored in
- bigarray C api changes - mechanical renaming
- Stream module now in camlp-streams package, fixed with
REQUIRES += camlp-streams
as needed - mem_send mem_recv are using GC internals which have changed with OCaml 5 and I am not qualified enough to fix it, so they are just commented out to make the branch build, ie somebody(c) should fix it properly. Also Netsys_mem.{color,set_color} are disabled too.
This is "make it work in anger" commit - I didn't take any care of backwards compatibility and probably should have split into separate commits, but here it is as it is :)