[Docs] Document Data Structures

[douglasg14b]

Hi!

I was trying to figure out the data structured used, and/or find example JSON outputs before using the lib, but it seems this is not documented.

Can the docs also include data structure docs? Especially given that this lib deals, primary, with turning markdown into a queryable data structure.

[rufuspollock]

@douglasg14b very good point. We'll try to include that.

[douglasg14b]

Thanks!