Brief overview?

[waldyrious]

@Benestar, can you provide a very short overview of how ask-wikidata works? It would help for contributors to add new patterns. Specifically, how does the parseQuestion function in src/parser.js work with the patterns/*.json files to interpret the question, and what exactly does the handleParsed function in src/index.js do with the result?

You could either provide this as a high-level quick overview in the README, or add comments to the relevant lines in those functions and json files.