test(router): disable a flaky test

modules/angular2/test/router/router_spec.ts

@@ -100,7 +100,9 @@ export function main() {
        }));
 
     // See https://github.com/angular/angular/issues/5590
-    it('should replace history when triggered by a hashchange with a redirect',
+    // This test is disabled because it is flaky.
+    // TODO: bford. make this test not flaky and reenable it.
+    xit('should replace history when triggered by a hashchange with a redirect',
        inject([AsyncTestCompleter], (async) => {
          var outlet = makeDummyOutlet();