Docs: more detail on Lwt_io.shutdown_server
Docs: more detail on Lwt_io.shutdown_server

See #259.

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c-cube/lwt,ocsigen/lwt,rgrinberg/lwt,rgrinberg/lwt,rgrinberg/lwt,ocsigen/lwt,rneswold/lwt,rgrinberg/lwt,rneswold/lwt,c-cube/lwt,rneswold/lwt,ocsigen/lwt,c-cube/lwt