non-blocking poll function
also stated fiels...
poll redraw fix on lcd
still implementing fields
non-blocking fixes and fields base
finnally activated dormant code aimed to support fields draw
much has to be done
Simple field implemented
Fields, Choose and Toggle templates added
menuField: change value of numeric variable
menuChoose: Use menu navigation to select variable value
menuToggle: 'click' to change variable value cycling a list a values
menuValue: menu prompt holding a value for variable set
TODO: avoid unnecessary redraw
fields definition macros now extrat template typename from target variable type
Fixed excessive redraw on GFX menu
Field range validation
etc...
minor fix, excessive redraw of exit option (GFX screen)
PCINT made compatible with arduino mega (Atmega2560)
and structured for wide compatibility by using arduino PCICR and PCMSKn map macros