stringToBoolean = function(val, defValue) {
		if (typeof defValue === "undefined") defValue = true;
		if (typeof val === "undefined") return defValue;
		if (val.toLowerCase() === "true" || val >= 1) return true;

		return false;
	}
Convert a string version of true/false/0/1 to a boolean. Returns
the second argument if first argument is undefined.
Returns true if no default value (second arg) is given and the
value is undefined as well.