This moves a handful of models and views specific to the Review Request

page into the new review-request-page JavaScript bundle. These models

and views aren't used in any other page, so getting them out of the

reviews bundle will help slim down the other pages and keep the code

more focused.
The models and views themselves now live in the RB.ReviewRequestPage

namespace.
Aside from updating namespace references, the files are not changed.

There's no conversion to ES6 or documentation updating, for instance, in

this change.

Unit tests all pass and all files were found.
Tested all applicable functionality of the review request page, including:

Replying to comments
Publishing replies
Interacting with reviews and changes