As a User, I want the system to remember that I read notifications when I click the Notices popup on the main Web UI, so that I don't have to get notified of those messages again.

This is one "write" function for the timestamps. When the alerts or notification UI is popped open, a POST request is sent from the browser to the MediaWiki server, handled by the Echo extension, to reset the last-read timestamp to now.

Priority: must have