Create a version with a serverless backend using AWS AppSync

[dabit3]

This issue is in regard to this thread.

The main idea is to do two things:

1. Replace the authentication type to Amazon Cognito using the Amplify CLI
2. Replace the back end with AWS AppSync

I will revisit this issue with more details & discussions later, but for now I wanted to get the conversation started to see if I can find people who would be interested in helping with this!

[Urigo]

@dabit3 we've just updated all the tutorial to the latest dependencies and released the full tutorial:

https://www.tortilla.academy/Urigo/WhatsApp-Clone-Tutorial/master

Now is the best time to talk more about next steps and stacks