Allows use of arbitrary length integers, where the following apply to all methods, except as noted:
The object $i remains unchanged.
Big integer strings (bints) have the form /^\s*[+-]?[\d\s]+$/.
All methods except bcmp return a big integer string or strings.
Embedded whitespace is ignored.
Output values are always in the canonical form: /^[+-]\d+$/.
The return value NaN results when an input argument is not a
number, or when a divide by zero is attempted.