Summary: Ref T4103. Ref T10078. This puts a user cache in front of notification and message counts. This reduces the number of queries issued on every page by 4 (2x building the menu, 2x building Quicksand data). Also fixes some minor issues: - Daemons could choke on sending mail in the user's translation. - No-op object updates could fail in the daemons. - Questionable data access pattern in the file query coming out of the profile file cache. Test Plan: - Sent myself notifications. Saw count go up. - Cleared them by visiting objects and clearing all notifications. Saw count go down. - Sent myself messages. Saw count go up. - Cleared them by visiting threads. Saw count go down. Reviewers: chad Reviewed By: chad Maniphest Tasks: T4103, T10078 Differential Revision: https://secure.phabricator.com/D16041