Fixing some worrying code rot. Why weren't these typos found before???? At a stretch , new version of uHAL is case sensitive

Documentation

This should only be minor tweaks.

Hack to determine whether the display is installed or not. If not avoid trying further communication by setting the displayPresent flag to FALSE

Can now activate ADAFRUIT backpanel. Still lots to do. Need to add switch to not use display if tabletop mode

Documentation

Added debug to I2CuHal2 to indicate when a slave fails to ACKNOWLEDGE (useful to see if a device is responding at all). Also started to expande the functions available for the LCD09052 display.