Introduce recent to Follow, as Account and other models have.
This change also adds specs for the scope and the dependents.

* Add render_views in more places

* Delegate methods from account to user with allow nil true, so that admin accounts show view renders when missing a user

* Use actual account instances in authorize follow controller spec

* Add routing specs for accounts followers and following actions

* Use more restful route naming for public account follow pages

Moves two actions:
- accounts#followers to accounts/follower_accounts#index
- accounts#following to accounts/following_accounts#index

Adds routing spec to ensure prior URLs are preserved.