The loadFromConfig variable must be a public
Read and write now work for I2C.

- Fixed Exception I2C define headers
- Changed read and write to write the register before continuing, the
  original way of doing it was not going to work because the way the I2C
  protocol works
- Updated the tests to reflect the new changes

issue #20
Merge branch 'testing' into hardware
Few tests for the GPIO class

The GPIO tests have been added, which have fixed the stupid error with
timeouts when constructing

makefile.common now uses -Wextra just to show more warnings
Added more GPIO tests
Working GPIO tests
Merge branch 'hardware' into testing