* lots of warning fixes; builds with -std1 on dec unix

    * lots of warning fixes; builds with -std1 on dec unix
        * aidepost.c, citadel.h, citmail.c, file_ops.c, msgbase.c, netmailer.c,           netproc.c, rcit.c, server.h, stats.c, userlist.c: use time_t where
          needed
        * control.c, room_ops.c, serv_chat.c, sysdep.c: use memset() instead of           bzero()
        * dynloader.c, dynloader.h, messages.c, server.h, sysdep.c,
          sysdep_decls.h: function pointer/prototyping fixes