Setup messages for async order validation

[btkostner]

This adds the needed bottle messages to move Hal and LP to async order validation over RabbitMQ.

This is a little different than what we normally do. First off, I wrote this like a grpc service. We make a request, and we expect a response. The only difference being this is async over rabbitmq instead of over grpc. Because of that, I put the two messages in their own file, and named them OrderVerificationRequest instead of the past tense OrderVerificationRequested like what we do with events. Interested in your thoughts about this request vs event naming @doomspork

[btkostner]

The alternative to this being we phrase it like an event so we end up with OrderVerificationRequested and OrderVerified messages