* Introduce WebSocket-based RPC v2
* go test: add -ldflags="-B gobuildid"
* No need to change the "controller.workerNotifier.Notify()" error message
* No need to modify Protocol Buffers/gRPC generated code
* rpcWatch(): explain that connection shouldn't be normally be closed
* Avoid "port forwarding failed: " repetition in error messages
* Improve comments and avoid repetition in IP resolution errors
* proxy.Connections(): require io.ReadWriteCloser instead of net.Conn
* Orchard Controller: implement an SSH server that acts as a jump host
* Issue a warning if the name used will be invalid in the future
* Further restrict uppercase characters in names in the future
The rationale is similar to https://github.com/kubernetes/kubernetes/issues/71140.
We won't want to munge the user's input and introduce subtle bugs doing
lowercase comparisons.
Nikolay Edigaryev