Add web front-end and fix API issues

node_modules/rxjs/dist/esm5/internal/operators/switchMapTo.js

@@ -0,0 +1,6 @@
+import { switchMap } from './switchMap';
+import { isFunction } from '../util/isFunction';
+export function switchMapTo(innerObservable, resultSelector) {
+    return isFunction(resultSelector) ? switchMap(function () { return innerObservable; }, resultSelector) : switchMap(function () { return innerObservable; });
+}
+//# sourceMappingURL=switchMapTo.js.map