Change Details

We need to investigate the technical details of the current watchlist and get a good understanding of it before making a plan for global watchlists. Acceptance criteria: * Add to the technical documentation at https://www.mediawiki.org/wiki/Manual:Watchlist so that all the relevant details of how watchlists actually work are covered there. In particular: What actually happens when you view your watchlist? What is the wl_notificationtimestamp column for?