Fixed problems handling passive connections in Remoting #2878

- Fixed potential race in EndpointWrite when TakeOff is processed
- Reenabled accidentally disabled gremlin due to changed defaults
- Fixed EndpointRegistry incorrectly handling passive connections
Merge pull request #1031 from drewhk/wip-2780-removal-of-old-remoting-drewhk

Removed remaining parts of the old remoting #2780