* [CHD-3312] [VA/Send Email] Fixed a fatal error when using the 'Send Email' action in Virtual Attendants with an address list variable as the 'To:' field.
* [CHD-3310] [VA/Orgs] Virtual Attendants can now use the 'Send Email' action on organization-based behaviors.
* [VA/Knowledgebase] Virtual Attendants can now use the 'Send Email' action on knowledgebase article behaviors.
* [VA/Time Tracking] Virtual Attendants can now use the 'Send Email' action on time tracking behaviors.
* [CHD-3315] [Platform/Database] Added an informative error message when the database connection disappears.  Devblocks will now gracefully shut down in this case.  Previously, this was giving vague errors about 'getVisit() on a null object', as Cerb would continue to try to process the request anyway.
* [CHD-3320] [Mail/Usability] Worked around an issue in Firefox where the reply textbox didn't auto-focus.
* [CHD-3313] [Mail/Setup/Reply-From] If there is no default reply-to address then the first result will be used.  This fixes an issue on some 4.x to 6.x direct upgrades where no reply-to address was flagged as the default, which caused various issues (inability to create workers because the welcome email failed, etc).
* [Sessions/Usability] Fixed an issue where PHP was expiring inactive sessions from the database after 24 hours regardless of the Cerb session cookie duration that was set in Setup->Security.  The cookie lifetime is now used when pruning inactive sessions, so using the "1 week" or "1 month" expirations should work properly now in all environments.
* [CHD-3308] [Mail/Keyboard/Usability] Fixed a few issues with keyboard shortcuts while composing or replying and using Ctrl+Shift text selection.  This particularly affected Opera.
6.3.1-release checkpoint
Merge branch '6.3.1' into stable