Address edge case where min > max
Address edge case where min > max

This can happen in two different ways for subtraction:

- the otherNumber is equal to min, then max is setup to otherNumber-1
- the otherNumber is equal to max and we don't allow zero so we reduce
  max by 1

In either case, we want to decrease the min value to match the max
value.

See #11

salcode/fastfacts,salcode/fastfacts