By default, it is set to "<code>\n0: Exit</code>".
Subclass may override with the preferred text or language specific content, or override it with settings obtained from the
configuration file. NOTE: the menu index for exit is FIXED to 0, and cannot be changed.
Note the state editor will display an input dropdown attribute called "Show Exit menu". This is used for selecting whether
to include the exit menu in the SMS menu message. This is used in cases where the exit menu is not be allowed, forcing the
user to select a menu item.
Syntax