removing superfluous file
moved function calls from core to config. Treating config as the scratchpad, may need to rename.
new function, calcs interest accrual for arbitrary number of years
removed superfluous parameter in the loop statements in several of the most recently written functions
fixed the one month interest calculator to bottom out at 0, so it no longer returns negative interest if the balance is overpaid
some new funcs. just started adding more component funcs to do a refactor of the higher level funcs to make them iterate over years instead of months
added a func to handle a static one year time frame of mortgage payments