1.1.0rc6

• add custom action command BEDLEVELVISUALIZER_LEVELBED to allow use with various custom config input options in Marlin (Configurationa_adv.h), ie CUSTOM_MENU_MAIN. Will initiate the command contained within the Update Mesh gcode script when received. Requires HOST_ACTION_COMMANDS to be enabled as well. Example menu item.

#define MAIN_MENU_ITEM_1_DESC "Bed Visualize"
#define MAIN_MENU_ITEM_1_GCODE "M118 A1 action:BEDLEVELVISUALIZER_LEVELBED"