Add web front-end and fix API issues

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

@@ -0,0 +1,13 @@
+import { mergeMap } from './mergeMap';
+import { isFunction } from '../util/isFunction';
+export function mergeMapTo(innerObservable, resultSelector, concurrent) {
+    if (concurrent === void 0) { concurrent = Infinity; }
+    if (isFunction(resultSelector)) {
+        return mergeMap(function () { return innerObservable; }, resultSelector, concurrent);
+    }
+    if (typeof resultSelector === 'number') {
+        concurrent = resultSelector;
+    }
+    return mergeMap(function () { return innerObservable; }, concurrent);
+}
+//# sourceMappingURL=mergeMapTo.js.map