Send data to the remote server in large chunks.
Send data to the remote server in large chunks.

Reduces a lot the sending time when running on slow CPUs.

git-svn-id: 5bd49132847c26fb0bf09d36ee8823e0080b2740@922 958fd67b-6ff1-0310-b445-bb7760255be9

salvis/qpsmtpd,vetinari/qpsmtpd,smtpd/qpsmtpd,sieutruc/qpsmtpd,sieutruc/qpsmtpd,msimerson/qpsmtpd,salvis/qpsmtpd,vetinari/qpsmtpd,priyadi/qpsmtpd,smtpd/qpsmtpd,msimerson/qpsmtpd,priyadi/qpsmtpd,priyadi/qpsmtpd,sieutruc/qpsmtpd