String.prototype.toNumber

@Description: Converts a numeric string into an integer or float
@File: String/prototype/toNumber.js
@Author: Paul Visco
@Version: 1.0 11/19/07
@Return: Number If the original value is an interger, an integer value is returned
@Example:

var myString = '12';
var num = myString.toNumber() +2;
//num = 14 //without running toNumber it would return '122'

var myString = '12.4';
var num = myString.toNumber() +2;
//num = 14.4 //without running toNumber it would return '12.42'