Optimization: Lazy Load your Messenger Implementation

[jamesmontemagno]

I would recommend following my "Lazy" loads for each. Else you are creating a new Task each and every time.

[cjlotz]

The task apis' are very cheap to create and they won't be used frequently in app, but I'll consider adding caching and lazy loading in a future update.

[cjlotz]

I've decided to not implement any lazy loading. The different Task implementations carry no state and have no initialization logic in their construction process. All state is passed into the Task when the relevant Messaging API called is made. There is therefore no performance overhead/initialization logic which warrants a technique like lazy loading and I'd therefore prefer not introducing the complexity of managing the state as part of the Messaging API.