Merge pull request #6 from Vido/master

 Extending the new RaspberryPi class
New implementation for RaspberryPi with the 3rd-part lib RPi.GPIO
Added _ prefix to board methods that are "friend"
Ghost tests passing
restructuring repo for setup.py implementation
getting ready to post to PyPI
getting ready to post to PyPI
minor tweaks after uploading to TestPyPI
changing release version to make PyPI happy about additions to README.rst
workaround for bug: cannot find README.rst when package is installed by root user in RaspberryPi
RPi pin_map.py example
simple examples with pingo.rpi
bump version number to 0.1.6
improved error message for RPi.GPIO dependency when using pingo.rpi
renamed research/ to experiments/
doctest digital.rst for UDOO passing
unittests for Udoo passing
atexit to Ghost. And a .vimrc the the project.

.vimrc will prevent \t and 4-spaces problems, and traling-white-space