ocaml: use Lwt.join instead of pick (wait for all jobs, rather than just first!)
ocaml: use Lwt.join instead of pick (wait for all jobs, rather than just first!)

timbertson/gup,gfxmonk/gup,gfxmonk/gup,timbertson/gup,gfxmonk/gup,timbertson/gup,timbertson/gup