Refactor platform detection to common module, and add I2C support.
Refactor platform_detect to Platform, add Pi revision detect function, and default I2C bus function.
Remove unnecessary logger.
Fix missed usage with platform_detect rename.
Fix bug with handling non-matching lines in pi_revision().
Fix issues with 16 bit read endianness by exposing explicit endian control.
Merge pull request #2 from adafruit/i2c

Add I2C support and refactor platform detection to common module.