Modernize Python

[mrkrause]

run.py and run_RmpRiTau.py both contain some obsolete Python.

Specifically:

• numpy.savetxt expects an array_like object, but is instead called with two 1D arrays, zipped together. This no longer works in Python 3 because it returns a zip object, rather than a list that can be coerced back into an array. Consequently, both run.py and run_RmpRiTau.py crash when writing data to a file.

• The plotting code in both files calls set_window_title, which is slated for removal in the next release of matplotlib.

[ramcdougal]

I don't think I ever fixed this... PR 4 wasn't merged but it can't be directly because the source repo is gone