mmm_control does not show usage when monitor is unreachable

[MikeG]

# mmm_control help
ERROR: Can't connect to monitor daemon!
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It would be nice to still include usage here. Example:

# mmm_control help
ERROR: Can't connect to monitor daemon!

Valid commands are:
    help - show this message
    ping - ping monitor
    show - show status
    checks [<host>|all [<check>|all]] - show checks status
    set_online <host> - set host <host> online
    set_offline <host> - set host <host> offline
    mode - print current mode.
    set_active - switch into active mode.
    set_manual - switch into manual mode.
    set_passive - switch into passive mode.
    move_role [--force] <role> <host> - move exclusive role <role> to host <host>
                                        (Only use --force if you know what you are doing!)
    set_ip <ip> <host> - set role with ip <ip> to host <host>
#