Adding David Evans notebook on Parallel Computing with updates to Pyt…

[mmcky]

…hon3

Adds

1. notebook
2. support files in mpi/

This incorporates updates to files for Python3

Issues

• [ ] Section on ipyparallel needs to be updated due to change in Jupyter

Questions

1. @jstac what naming convention should we adopt for notebooks that require support code. This notebook for example currently has code in a folder called mpi/?

[mmcky]

There is still an issue with ipcluster start command in my latest Python3.5 Anaconda distribution.