Enhance product view

* fix the layout so it has the analyzer navbar on the left
* switch the form to use .as_p() which makes it a tiny bit easier to use
* tweak the view code so that it makes it easier to update existing
  products
* add some "helpful" directions so it's a little clearer as to what's
  going on

This improves on what Ian did just to make it a little easier to use.

r?
This allows us to pass a pk in the querystring which will cause the form to load that product's details.