Saving G29 Bed Level Correction Matrix to EEPROM

[AbuMaia]

Now that we have this mod to save the G29 matrix for an entire print session (or longer), it is no longer necessary to add a G29 to the start gcode when slicing. However, those of us who run our printers standalone, we need another way of running the G29 when we change a setting or a glass plate. I believe that many who run their printer standalone have an LCD display on their printer. Here's what I did to add G29 to the LCD menu:

In ultralcd.cpp, find MENU_ITEM(gcode, MSG_AUTO_HOME, PSTR("G28"));
Just after it, add MENU_ITEM(gcode, MSG_BED_LEVEL, PSTR("G29 n5"));

In language.h, find #define MSG_ENDSTOP_ABORT "Endstop abort"
Just after it, add #define MSG_BED_LEVEL "G29 Bed Level"


Roxy, I ran into an error adding your code:

ConfigurationStore.cpp: In function ‘void Config_PrintSettings()’:
ConfigurationStore.cpp:129:65: error: void value not ignored as it ought to be
plan_bed_level_matrix.debug("\n\nBed Level Correction Matrix:")
^ (this caret should be under the closing parenthesis after "Matrix")

That is the only error. Commenting out only the added code block from Config_PrintSettings let it compile cleanly.