Test fixes for UrlParser, HtmlElementCreator

Also fix old parseQueryString and alias it to getQueryStringParam

tests/MathHelpers.test.js

@@ -24,6 +24,8 @@ describe("roundPrecision", () => {
 	it('should round numbers to a given precision', () => {
 		let val = roundPrecision(10.1234, 2);
 		expect(val).toBe(10.12);
+		// @ts-ignore
+		expect(roundPrecision("abc", 2)).toBe("abc");
 	});
 });