Release 6.20.2: new configuration option com.openexchange.mail.filter.useSIEVEResponseCodes for the mailfilter bundle

[changerequest]

The new configuration option com.openexchange.mail.filter.useSIEVEResponseCodes in /opt/open-xchange/etc/groupware/mailfilter.properties can be used to interpret the SIEVE response code as defined in RFC5804.

This is an optional switch which usually must not be changed.
The default is false.