[Battlemesh] JSON data interchange format for networks

[Juliusz Chroboczek]

> https://github.com/interop-dev/json-for-networks

A few comments, from a Babel perspective:

 - the name of the metric is "routing_metric" and "metric", depending on
   the object; it should be "metric_type" in both cases;

 - the value of the metric is "cost", it should be "metric";

 - there should be optional fields "neighbur_metric" and "neighbour_cost";
   normally, metric = neighbour_metric + neighbour_cost, but that's not
   necessarily the case if using a non-additive metric (such as Babel's Z3
   metric);

 - there should be optional fields "rtt" and "channel".

For an example of the cool things that can be done with the additional
fields, please see

   http://babelweb.wifi.pps.univ-paris-diderot.fr:8080

-- Juliusz