* [Virtual Attendants/Migration] Fixed an issue in the 5.4.0 migration script where Group Inbox Routing rules were not properly converted to Virtual Attendant group behaviors if there was only a 'To/Cc' condition.
* [Virtual Attendants/Migration] The 5.4.0 migration script will now create separate 'To:' and 'Cc:' header checks when converting Group Inbox Routing 'To/Cc:' rules to Virtual Attendant behaviors.  Previously it just created a 'To:' header check.
* [Update/Plugin Library] Fixed an issue in 4.x and 5.x migrations where the Plugin Library attempted to download its updates before the 5.7.0 patch created its database tables.  This didn't interrupt the upgrade process, it just logged an error.
6.5.4-release checkpoint