Documentation

[CarloLucibello]

We should use Documenter here, i can submit a PR as soon I can spare some time

question: should this repo have its own github page or should it have a section in LightGraphs' one? @sbromberger

[sbromberger]

It will need its own, I think. Otherwise we'll have to combine the docs with LG's and that will get messy when it comes to updates.

[sbromberger]

and yes - agree that we should move to Documenter.