Proxyless error due to race condition

[ColinRobbins]

The TRV proxy code creates a UDP listener to receive data on TRV status.

However, to send commands to a switch, a temporary listener is also created on the same port to get the command status response.

This it is "random" which listener sees the response, creating errors in the logs, even in the command works.

Code needs refactoring to use a single multi-purpose listener.

[ColinRobbins]

Fixed