Using %matplotlib notebook to render plots.
I made the g-h filter chapter work. There is a very good chance
I broke the other chapters. Need to push to really find out.
This code did not work for Python 2.x becaus I was not
importing from future. While I was altering all the files
I updated the header to include license information.
User ulenka on gitter suggest changing the color for the
residual line. I found my changes garish, so I switched
to a thicker black line and changed the grids to dotted.
