GitLab

Move ResponseProgress to the types package and extract some testing functions to testutil

Make the request manager actually inject responses from the network, and perform a selector
verification

Convert GraphSyncRequest and GraphSyncResponse to structs, track by value, pass directly into add
methods on GraphSyncMessage

Handle failed request status codes from server and pass on errors

Add a channel of asynchronous errors instead of only an initial synchronous one

Create a manager for outgoing requests