We have a lot of new UI and user experience changes in RB6, so it was

necessary to do an overview of the docs to make sure everything is up to date.

This change updates any screenshots that were affected by our UI changes, and

fleshes out some documentation for file attachments and review requests.
Note: The screenshots in this change are not perfect and are just

      placeholders. They should be replaced with new screenshots in a later

      change.

Built the docs, made sure the new screenshots looked good, checked that all new

refs worked, and checked for spelling errors.