Bugfix: conversion scale maximums are too short and rename scale to digits.

Bugfix: conversion scale maximums are too short and rename scale to digits.

The "scale" max is not consistently correct.
In some cases I have the signed one number less than the unsigned version (which should only be true for the binary representation).
In other cases, I should have a larger number because it doesn't fully represent all digits.
This is likely a mistake resulting from my misuse of the term "scale".

The way I am using "scale" is not exactly correct with the meaning of the word.
Rename "scale" to "digits" to better represent what this variable its related defines are for.