Python script now 10x better, added features to allow fitting of a parabola

Changes to python script roughly:

 - Draws graphs in realtime
 - Sends console input to arduino
 - Threaded for awesome performance and weird bugs!

Changes to one_axis_balance.ino roughly:

 - Added function to allow fitting of a parabola to the data. This should
       allow the derivative term to be smoothed based on previous data.
 - Added fifo class to allow the last n data points to be recorded for the
       aforementioned analysis.