Improve the documentation of the DataStoreInterface
Description
This MR adds docstrings to the DataStoreInterface
, to explain the purpose of each of the methods in the API. It also adds type annotations to all the methods in that class, to make the method signatures easier to discern at a glance.
It also adds some documentation on the "Notes for Developers" page on what is required to implement a new backend for the DataStoreInterface
.
Solves #233 (closed).