The operator + - and * are non method functions now
Changed the word PASSED to FAILED when test is failing
Created a Sensor interface to be used with others

Added accelerometer to implement this interface
Inverted values added to the Hardware
Updated the constructor and fixed the tests

The servo was not setting the values when not inverted, bad bad bad.
This is now fixed
Fixed * to & for getServo in all classes

Updated the examples file to reflect the recent changes
Accelerometer now returns Pitch and roll
Merge branch 'sensor' into testing

Juicy updates need to make sure all works as a whole system