1) Fix of stepper control timing
2) Load / restore baby stepping after 9 point bed leveling using
the planner instead of the questionable baby stepping routine.
Improvement of the menu system: Use a shared menuData union to preserve
memory. Adaptation of baby stepping and edit menus to menuData.
Improvement of the "Toshiba FlashAir" status display. Don't force IP
address query on each display refresh when in the "Support" menu.
Bugfix of the baby stepping menu: Show the correct value instead
of zero when the baby stepping menu is entered.
New feature: Bed leveling adjustment at left / right / front / rear side.
The bed adjustment feature is accessible from the Settings menu
and as L R F B codes of the G80 code.
difference from the reference value stored in the EEPROM.
Lowered the speed of lowering the Z axis during the XY calibration
from 0.5mm per zig-zag search to 0.2mm to avoid the nozzle scratching
the bed if the PINDA sensor is mounted too high.
Improved the display routine to break the interpunction from the end
of a sentence. While the result may not be typographically correct,
more fits onto the screen.
"M115 Umajor.minor.revision-flavor" will trigger a dialog
on the display if the "upgrade" firmware version number is higher
than the current version number.
