ContentType conflict between edge_client.proto and edge/messages.go

```proto
# edge_client.proto

  UpdateTokenType        = 60800;
  UpdateTokenSuccessType = 60801;
  UpdateTokenFailureType = 60802;
```

```golang
// edge/messages.go

	ContentTypeConnInspectRequest  = 60798
	ContentTypeConnInspectResponse = 60799
	ContentTypeBindSuccess         = 60800
```

I'd prefer to move all constant definitions into protobuf file