2002-05-28  Mark McLoughlin  <mark@skynet.ie>

        Fix #82959 by invoking DiscardCommand every time we
        forget a RestartCommand. This assumes every client
        knows to re-save its session data every SaveYourself,
        so we also check that a client is doing this.

        * manager.c: (free_client): free last_discard.
        (run_command_prop), (run_command): split run_command into
        two methods. run_command_prop invokes a command directly
        from and SmProp.
        (reincarnate_client): also copy session_saved.
        (process_save_request): save the DiscardCommand in last_discard
        before sending a SaveYourself.
        (maybe_run_discard_commands): impl method to run DiscardCommand
        every time we 'forget' a RestartCommand.
        (save_yourself_done): use it here.

        * command.c:
        (prop_dup): move and rename to gsm_prop_copy in prop.c
        (client_reasons), (client_property), (command): upd.

        * headers.h: add last_discard and session_saved members to
        Client structure.

        * prop.[ch]: (gsm_parse_vector_prop), (gsm_prop_copy),
        (gsm_array8_compare), (gsm_prop_compare): implement these
        methods.
        (find_vector_property): use gsm_parse_vector_prop.

        * util.[ch]: (gsm_compare_commands): implement this.

        * save.c:
        (write_one_client), (read_clients): set session_saved here.
        (delete_session): use gsm_compare_commands.