Improve documentation, including examples

[amotl]

Problem

The library is a wrapper around the OPS API, and the difficulty at present is that there is no tutorial or examples scripts to showcase the different methods and responses. So you'll have to refer back to the OPS reference guide most of the time. Perhaps you want to open a discussion item on a specific topic or an issue, whichever you think is appropriate?

Originally posted by @mattkeanny in #81 (comment)

/cc @mattkeanny, @CholoTook

References

• Documentation with examples #83
• README: Educate about retrieving the document's "description" and "claims" #138