Simplified the overridden render method.

Removed the private _prerender function since it was unnecessary.
I've also reformatted some of the comments to better fit on 80 column
display.
Filling out testing and README.md for the project.

Found two issues with the lib itself.  First was a typo and the second
was a bad reference to 'this', which now that this plugin exists takes
on a different context from what was in the previous code.

Added testing based upon the framework setup in Backbone.Subviews with
three tests to cover the funcitonality of this small library.

Filled out the README.md file, keeping it simple.  I've yet to see the
rendered markdown, so I expect there to be some tweaks to come.