Make ParseError construction more lenient

JSON test 'should have statusCode in err' requires an instance of
ParseError to compare to but has no opts or data to pass. This commit
makes those arguments optional allowing for empty ParseError
construction.

index.js

@@ -340,7 +340,9 @@ function stdError(error, opts) {
 
 got.RequestError = createErrorClass('RequestError', stdError);
 got.ReadError = createErrorClass('ReadError', stdError);
-got.ParseError = createErrorClass('ParseError', function (e, statusCode, opts, data) {
+got.ParseError = createErrorClass('ParseError', function (e, statusCode) {
+	const opts = arguments.length > 2 && typeof arguments[2] !== 'undefined' ? arguments[2] : {};
+	const data = arguments.length > 3 && typeof arguments[3] !== 'undefined' ? arguments[3] : '';
 	stdError.call(this, e, opts);
 	this.statusCode = statusCode;
 	this.statusMessage = http.STATUS_CODES[this.statusCode];