Add web front-end and fix API issues

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

@@ -0,0 +1,15 @@
+import { concat } from '../observable/concat';
+import { take } from './take';
+import { ignoreElements } from './ignoreElements';
+import { mapTo } from './mapTo';
+import { mergeMap } from './mergeMap';
+import { innerFrom } from '../observable/innerFrom';
+export function delayWhen(delayDurationSelector, subscriptionDelay) {
+    if (subscriptionDelay) {
+        return function (source) {
+            return concat(subscriptionDelay.pipe(take(1), ignoreElements()), source.pipe(delayWhen(delayDurationSelector)));
+        };
+    }
+    return mergeMap(function (value, index) { return innerFrom(delayDurationSelector(value, index)).pipe(take(1), mapTo(value)); });
+}
+//# sourceMappingURL=delayWhen.js.map