Dynamo IT & IO Layer v0 (#84)

* Dynamo IT & IO Layer v0

This diff adds 2 _extremely_ WIP components:
1. A basic IO layer that uses Hyper and a pure Rust signer. This will change significantly over the coming days.
2. A rudimentary Dynamo DB integration test that creates a table and verifies that it exists.

Neither of these is anywhere near final, but, rather, these are intended as a starting point for discussion.

* Fixup tests