[Migration/Code Cleanup] The 6.7 migration will now automatically remove old style 'devblocks_cache---*' files from storage/tmp/.  These wouldn't be deleted during an update because the filesystem cacher now deals with 'cache--*' prefixes.
* [API/Worklist/Export/Placeholders] Record IDs are now available as placeholders through the API and when exporting worklists.
* [CHD-3421] [Sessions/Usability] The expiration on worker sessions is now automatically extended during activity.  Previously, a cookie was set when the worker logged in, and if sessions had an expiration of '1 week', then the cookie would obnoxiously expire at that future time even if the worker happened to be logged in and actively using Cerb.  Now the session expiration options are all based on the time elapsed since the last worker activity.  If sessions are set to expire after a week of inactivity, then any activity by that worker will extend the expiration by another week.
* [Security/Sessions/Setup] Added two new shorter duration session expiration options to Setup->Configure->Security: "after 6 hours of inactivity", and "after 12 hours of inactivity".  These are useful now that session expirations only count a continuous period of inactivity.
[Code Cleanup/Worklists/Export] Worklist export cursors are now removed from the session after the export has completed.
* [CHD-3324] [Setup/Workers/Usability] Administrators can now change worker passwords from Setup->Workers.  In some situations, worker email addresses are also managed by Cerb, so having account recovery information sent there doesn't work.  If the password field is left blank on a new worker, then a temporary password will be generated and emailed to them.  Some login authenticators (e.g. OpenID, LDAP) will ignore the local password during the login process.
[Code Cleanup] Fixed a PHP error when a session exists but the originating worker doesn't.  This shouldn't happen in most cases.
* [Setup/Workers] When a worker account is deleted, their sessions will now be properly deleted as well.
* [CHD-3386] [Calendars/Search/Usability] Quick search can be used to filter by calendar on calendar event and recurring event worklists.
6.7-dev checkpoint