config/plugins: added fcrdns, do not reject by def
config/plugins: added fcrdns, do not reject by def

set plugins behavior in sample config file to not reject by default

sieutruc/qpsmtpd,salvis/qpsmtpd,priyadi/qpsmtpd,priyadi/qpsmtpd,msimerson/qpsmtpd,sieutruc/qpsmtpd,sentinelleader/qpsmtpd-dev,salvis/qpsmtpd,msimerson/qpsmtpd,sieutruc/qpsmtpd,smtpd/qpsmtpd,priyadi/qpsmtpd,smtpd/qpsmtpd,sentinelleader/qpsmtpd-dev