Posts command event to main window

    Command events propagate.

    Parameters
    ----------
     * msg_cls: class
    \tMessage class from new_command_event()
     * kwargs: dict
    \tMessage arguments

def post_command_event(target, msg_cls, **kwargs):
    """Posts command event to main window

    Command events propagate.

    Parameters
    ----------
     * msg_cls: class
    \tMessage class from new_command_event()
     * kwargs: dict
    \tMessage arguments

    """

    msg = msg_cls(id=-1, **kwargs)
    wx.PostEvent(target, msg)