Minor bugfixes / improvements:
! Fixed: deadlock on insufficient resources
! Fixed: race condition in ssl_plugin
! Fixed: minor memory leak on configuration reload
! Fixed: recursion detection was not working
! Fixed: %n for IPv6 in logging terminates log record
! Fixed: reverse PTR validation (required for dnsauth)
! Fixed: error on external 0.0.0.0 for NOIPV6 (light version)
+ Better support for IPv6 in ftppr