Raspberry Pi Quadrature Encoder SFunction

This code is port of Giampy's encoder SFunction from Arduino using the WiringPi library.
It has support for multiple encoders.

Other device driver block, and the hardware it was run on is available at our website:

http://minseg.webs.com/downloads

A complete library for Arduino and curriculum is available here:
http://minseg.com/pages/downloads

coming soon:
- MPU6050 gyro accelerometer
- HMC5883L magnetometer
- FreeIMU driver

and others!

This work is part of the Mechatronics curriculum at Rensselaer Polytechnic Institute.