mini-ndn

Per #5362, it is possible that in the next few years, the existing Mini-NDN design will be reliant on an LTS version of Ubuntu which is no longer formally supported. One proposal was to swap from a reliance on Mininet to the Containernet project (https://github.com/containernet/containernet), which is being kept more up to date. However, such a change will pose a number of challenges in terms of development time and compatability. We should ideally assess what features are and are not compatible with this approach, as well as what other benefits could be gained from this swap.