encrypted datastore

Simple placeholder implementation of the sketched out datastore implementation.

Implemented using a library called Twirp, which is very like simplified GRPC. It starts from a protobuf definition like GRPC, but is simpler, and runs over HTTP/1.1 rather than having a hard requirement on HTTP/2.

Requirements

• Go 1.8+
• retool
• protoc 3.5.0+

Using retool

Experimenting here with using retool to handle vendored build time binaries (like dep and the protobuf stuff). We add tools using the retool binary which adds a _tools folder which I've also vendored. After that the required approach is that for tools within that dir we run them using retool do <command> which ensures everyone is using exactly the same versions.

Make tasks

Currently v.minimal - I just have a gen task which uses the retooled protoc binary to rebuild the interface implementations from the protobuf file.