- changed range of flex from 2 -> 5 to 1 -> 5

- for coco function, changed association list so that verylow and low
  map to correct integer values (1 and 2, respectively)

- fixed all slopes for scale factors, effort multipliers, and defect
  removers

- simplified my-random-int by removing division by 1000

- changed maximum value for b from 1 to 0.1

- changed scale factor defect introduction lines from hinged-lines to
  pivoted-lines

- removed references to the "thing" struct

- fixed zap's improper use of rassoc

- fixed pcap special case (slope of 0 in requirements phase)

- fixed comment for the interpolate function

- coded defects and threats models

- coded energy function calculation