Check Interfaces in add_interface

[andrew-hoff]

Is there any reason why you don't call check_interfaces here? Would that not reduce latency when adding a new interface at runtime? A bit of experimentation on my part seems to show reduced latency when I make that change. That having been said, I'm new to this repo, so I might be misinterpreting expected behavior.

[jech]

Good catch, fixed in 3d8aec4. (I'm scheduling an interface check 200ms later, since checking interfaces for each new interface would cause quadratic behaviour at startup.)

[andrew-hoff]

Great, thank you!