Generate documentation for traversal, mutation and filter methods

[fkling]

To know which methods are available, one has to to look at the source code. It would be cool if we could organize the method definitions in such a way that it makes it easy to auto generate documentation from the source.

[juliankrispel]

That would be very nice indeed!

[DrewML]

@fkling did you have any ideas for what kind of tooling you'd like to use to accomplish this? I think this would go a long way towards lowering the barrier to entry.

The method I've seen used most frequently is JSDoc comments. I think the problem there, though, is that you either need to be super strict about keeping the comments up to date, or have linting rules in place to try and catch things like undocumented or re-ordered arguments.

[DrewML]

Submitted a start on this work in #146.