Improve documentation / add option to output parameter names

@nrbertin brought up a good point while he was using the python bindings that it would be nice to see what the property names are for each model. We are definitely lacking in this area, and the only place that I believe has all the parameters labelled is my script for ExaConstit: https://github.com/LLNL/ExaConstit/blob/exaconstit-dev/scripts/ecmech_prop_file.py

So, my suggestions would be to add a new function that outputs the model parameter names in a human readable format rather than the blob of numbers that getParams would return. This call should also be able return the names and values if they've already been provided.

I'll see if I can't get to this at the start of the new years as part of improving documentation through-out the code.