This change fixes up some issues with our typing and some issues exposed

by adding typing:

In our review request data templates, the initial value of the

submitter link was being added to the review request, but it really

  only belongs on the review request draft.
Added the url field to the review group resource data definition.
The types for several things inside the review request attributes were

  incorrect (should have been ResourceLink[] instead of string[] or

  ReviewRequest[]).
Types throughout the review request fields implementation had some

  errors, especially typing for methods.

Ran js-tests.