Black-box testing of ng_netapi modules

Hi, since two days ago we have a module to black-box test ng_netapi modules: ng_nettest. I’ve PR’d tests for UDP as an example for that [1] (there are still some issues) and wrote a wiki page on how to write tests [2]. Please consider testing the other ng_netapi modules with that.

Cheers, Martine

[1] [2]