Fixing program memory attribute for Canvas files.
Making SPI_STC a SPI::Slave class friend for OOP ISR.
Improve handling of internal pullup for External Interrupt Pins.
Refactoring LCD Menu class; renaming lists and restructuring print.
Adding data type for general pointer to program memory data.
Improving OWI class to better support parasite power on 3V3 and 8 Mhz.
Adding Cosa to Arduino API mapping; digitalRead/Write, analogRead and pinMode.
Remove compiler warning on program memory.
Remove compiler warnings on program memory.
Fix return value from state transition functions.
Remove compiler warnings on program memory.
Refactoring SPI class to allow multiple devices with different settings.