Changes to the Cyrus IMAP Server since 2.4.17-caldav-beta5

      * RSS module now produces Atom 1.0 output rather than RSS 2.0 (we
        prefer IETF standards) 
      * PROPFIND/REPORT allprop/propname requests are now supported 
      * unixhierarchysep is now supported by all HTTP modules 
      * Completely rewrote write_body() - Range requests are now supported
        on non-chunked Content-Encoded data 
      * Added cache control response headers where appropriate to make
        Redbot happy 
      * Fixed handling of telemetry log file descriptors and truncation 
      * Allow GET on calendar collections for "exporting" entire calendar 
      * Fixed POST on calendar collection (add-member) 
      * Fixed parsing of calendar-query filter 
      * Added several CalDAV/iCalendar validation checks based on
        CalDAVTester results 

Changes to the Cyrus IMAP Server since 2.4.17-caldav-beta4

      * Always verify authorization credentials supplied by the client (a
        proxy may be reusing an existing connection as a different user) 
      * Don't bother supporting Digest qop=auth-int since no clients seem
        to use it 
      * Don't show addressbook mailboxes in IMAP LIST output 
      * Plugged leaked memory found by Valgrind 
      * Better handling of request/response bodies 
      * Added httpprettytelemetry option
      * 
      * Added httpallowcors option (Cross-Origin Resource Sharing)
      * 

Changes to the Cyrus IMAP Server since 2.4.17-caldav-beta3

      * Plugged leaked memory found by Valgrind 
      * Rewrote list_feeds() to not use memmem() 
      * OPTIONS method can be used without authentication 
      * Better handling of Connection:keep-alive 
      * Added httpallowedurls option
      * 

Changes to the Cyrus IMAP Server since 2.4.17-caldav-beta2

      * Fixed security bug where a user-agent could access files outside of
        httpdocroot. 
      * Changed annotation entry name scheme to be
