Update to use Cloudant instead of MySQL

[krook]

When I first created this, I used a relational database to show the REST CRUD mapping for a system many developers were already familiar with. That made sense to me from an API point of view.

But, to make this truly serverless and auto-scalable, the backend should be as well. Updates will be a little more complex in Cloudant, but that's the only downside. It also has the benefit of being Lite account compatible.

FYI @dokun1 @jthomas

[dokun1]

Having just delivered this lab to a client using MySQL, I'd be bummed if it changed soon! I don't disagree, though. I just wish Cloudant had an easier API to work with...or we just offered a free-tier of it 🤔