unit test coverage

[bruceravel]

The unit testing framework is certainly helpful, but it does not cover everything in the code. Perhaps the stuff it covers is not super important for the EXAFS mission of this project....

Some examples:

• There are no tests of the OVERLAP card ("card"! I cannot believe we are still using that word in 2014!). Problematic, I suppose, but I don't think that I have used Feff's overlap thingie in the last 20 years.
• There are no tests that include any of the sigma^2 or cumulant stuff. Of course, I think that including such things at the level of Feff makes data analysis more confusing, so I could be comfortable with simply disabling those bits of the code.
• There are no tests that cover things like ION, FOLP, or AFOLP.
• There are no tests that cover non-Hedin-Lvndquist potentials.
• There are not tests to exhaustively cover all the edges.
• A bunch of other crazy stuff -- grids, JUMPRM, INTERSTITIAL, and so on -- is not covered.