* Replace current_user.id with efficient_current_user_id in high-leverage areas
* Update name of efficient_current_user_id
* Replace user_signed_in? in pageviews
* Remove unneeded ?
* Reorganize PageViewsController
* Add domain and path to PageView model
* Add before_create callback to populate domain and path
* Add list of referrers to AnalyticsService
* Add referrers to the UI
* Remove useless referrers card and tweak table line height
* Add referrer stats to article stats page
* Add not null and empty default to domain and path
* Refactor JS analytics client
* create_list is a step back here
* Revert "Add not null and empty default to domain and path"
This reverts commit bc02440076047a887c65d300bccd4661ecc8ffd0.
* Add index on domain concurrently
* Make the script more robust