Continued segregating the email protocol tests, into their own protocol
based ranges, in preparation of adding more e-mail related tests to the
test suite.
Follow up fix to commit 62bd217464 to cater for servers that don't
respond with a 250 in their EHLO responses. Additionally updated the
SMTP tests to respond with a 250 response code as per RFC5321.
They were all wrong previously since none used the <brackets> they
should for MAIL FROM. Now libcurl adds them itself if the app doesn't so
they end up wrong less easy.
