encoder:
--------
* Added docs containing the connection plan for the encoder.
* Added lib pinchangeint for additional interrupt pins.
* Added src/AQ.h for general definitions
* Added src/AQArray.h a common template array.
* Added src/AQHashMap.h a common template hash map.
* Added src/AQAbstractSignalHandler.h base class for all kinds of signal handlers
* Added src/AQSignalHandler implementation of an AQAbstractSignalHandler
* Added src/AQSignal.h signal class for signal/observer patterns.
* Added src/AQEncoder.h(.cpp) a wrapper for encoder handling.
* Added basic encoder handling to the main.cc
Merge branch 'encoder' into dev