Updates README
First draft of the quickstart guide
Warns the user about the 'no duplicate corpora names' rule in the quickstart guide
Extends the quickstart guide to show the properties list

This also includes an example on how do download the freqdist for a document.
Changes quickstart guide from markdown to rst

This means we use only one markup language for our documentation.
Fixes bug in quickstart code
Adds a link to the quickstart guide in the README file
Merge branch 'feature/tutorial' into develop