Extract out deployment rollout and add tests

config_app/js/services/services.types.ts

@@ -1,10 +1,13 @@
 export interface AngularPollChannel {
-    create(scope: { '$on': Function },
-           requester: (boolean) => void, // function that receives a callback to continue or halt polling
-           opt_sleeptime?: number
-    ): PollHandle,
+    create: PollConstructor
 }
 
+type PollConstructor = (scope: MockAngularScope, requester: ShouldContinueCallback, opt_sleeptime?: number) => PollHandle;
+type MockAngularScope = {
+    '$on': Function
+};
+type ShouldContinueCallback = (boolean) => void;
+
 export interface PollHandle {
     start(opt_skipFirstCall?: boolean): void,
     stop(): void,