NoSQL database support

[matthewwardrop]

Currently we only support SQL databases; but it maybe interesting to think about adding a generic NoSQL database backend, which can be subclassed for specific databases like MongoDB or DynamoDB. We will probably think about this post 1.0.0.

@djKooks This would make your use cases feasible too.

[kination]

@matthewwardrop Seems good!

[harsham4026]

@matthewwardrop can we add the support for Azure Data Lake as well?