go/neo/proto: Kill outdated TODO

- Regrouping messages would change their message codes, thus introducing
  backward compatibility breakage.

- The protocol itself is currently kind-of documented in separate
  document here:

  https://neo.nexedi.com/P-NEO-Protocol.Specification.2019?portal_skin=CI_slideshow

go/neo/proto/proto.go

@@ -57,9 +57,6 @@ package proto
 //go:generate sh -c "go run protogen.go >zproto-marshal.go"
 
 
-// TODO regroup messages definitions to stay more close to 1 communication topic
-// TODO document protocol itself better (who sends who what with which semantic)
-
 // NOTE for some packets it is possible to decode raw packet -> go version from
 // PktBuf in place. E.g. for GetObject.
 //