Don't record redirects when the notrack URL var is set
Refactor tracking flow

Separates visitorId cookie setting from visit object creation
into two steps, since we want to have or update the visitorId
cookie, even though we might not track every redirection.
Render all lists with shortlink

Includes ?notrack=1 in curator tools, to prevent those clicks
from being tracked.
Merge branch 'notrack-shortlink-from-curator-tools'