Added Hale tutorial, updated README

Summary of Changes:
Added a Tutorial

Cleaned json in spec
Rewrote section on render
Now supports "enctype" and "request_encoding" as two separate fields
Changed "enctype" default
Cleaned up text for "options"
In looking at the Hale document and what the client would interpret it as, they seem to be the exact same thing. I think the point was to give a simple example of how _meta works to DRY things. Am I missing anything? I see no difference between them.