Add shortcut to join a match, requested by users.

    sub.add_argument('events', nargs='*', default=[], help='The log events to put in file.')

@register_parser

def subs_r(subs, prefix):

    """ Subcommand parsing for log """

    desc = f"""To register for a pvp event setup in the channel.

**{prefix}r**

        Join the existing pvp event in this channel.

    """

    sub = subs.add_parser(prefix + 'r', description=desc, formatter_class=RawHelp)

    sub.set_defaults(cmd='Match', subcmd='join')

@register_parser

def subs_match(subs, prefix):

    """ Subcommand parsing for match """