Refactoring thread

Fair warning: this code is not intended to run just yet. As I was refactoring the functions I realized I had questions for Dan and Co. and decided to put them up on github in order to avoid another long email thread. I'll try to tag people in specific comments to make those salient to relevant folks.
As far as I understood it, the ``feimax`` variable is coming from Plan X currently. It makes sense that if it were read in from the PUF it should be zero. I will make our ``feimax`` entry in the Plan X json file the same as it is in the SAS code and will resolve all future discrepancies similarly.