a bug in `compare` with a negative argument

[Yaffle]

var crunch = new Crunch();
var a = crunch.parse("-9999999999999999");
var b = crunch.parse("0");
var c = crunch.compare(a, b);
console.log(c); // 1, should be -1

P.S.
May be transformIn is needed for compare.

[vukicevic]

Fixed in pull request #26