Added updated arduino.h in new clean branch
Added PIO mappings in arduino.h
Renamed copypasted ifdefs in arduino.h for consistency
Included pio.h that already has port defines
Defines changes for DACC, ADC

Made changes to the defines for DACC, ADC pin mappings so they make use
of adc.h and dacc.h and their respecpective tests
Added missing LED-pin and some comments