Double render fix

Reducing the calls to the view creation to either call `render` on the client side or `attach` on the hydration step.  This should save some lifting in the view helper as it only needs to pass through a div with the data needed for the view, rather than creating an instance of the view and destroying it.

This also fixes a memory leak in the `initialization` step in the handlebars helper where it was setting all of the `listenTo` scope incorrectly (now they're not even being called).

This will _not_ be a breaking change from `rendr-handlebars` and will continue to function the same way if that package isn't updated.
yeah - $el.attr sets an attribute in the DOM, $el.data seems to not.  While I was writing the tests the $el.data('view-attached') was always coming back as `undefined`, whereas it is `true` with `attr`.