Issue #6 - reduced the API for retrieving/storing documents. I don't think there's any need to have separate API for different types of gets. Files are also uploaded using the same API and everything is referred to as a 'document'. When requesting a document, the response will be the contents of the document or an JSON object describing error - the document will no longer be encapsulated in a JSON document. This makes it easy to treat text and files the same. Also added gzip to the storage/retrieval of documents.