TestLanTcpPlugin that supports BRP

When running two or more connected instances of the application for interactive testing, it is a bit annoying that it can take very long for the contacts to be actually connected and able to exchange messages. I had thought enabling the LAN plugin would help, but since the LAN plugin does not support BRP, adding contacts at a distance does not work via that plugin. Now I had the idea that we might add a new plugin TestLanTcpPlugin that allows rendezvous via LAN and would only be used in test setups such as this.

I'm wondering how much effort this would be.

I can see supportsRendezvous() probably needs to return true and then createRendezvousEndpoint() would need to be implemented. Not sure how much of TorPlugins implement could be reused there. @akwizgran do you an assessment how much trouble this all would be?