add I2C register map
add I2C register map
add I2C register map
add I2C register map
Merge branch 'i2c' of github.com:deanrock/mchck into i2c

Conflicts:
	toolchain/include/mchck.h
toolchain: fix i2c register/enum names and indent
Added missing gpio pin definition
backend-driver: RuntimeError is misspelled
Merge pull request #71 from bgamari/master

backend-driver: Fix typo
examples: add broken i2c code
programmer: use right class in test code
lib/printf: add fixed point support
programmer: make errors more friendly