Code review

You can find my comments in this pull request.  Feel free to delete this pull request once you're done with my comments.  Also feel free to argue with me. :)

I think it's a good project to have an easy to use smtp library for Haskell, that supports TLS.  But tying it to gmail seems to be a bad idea.  Port 587 + starttls + authentication is the industry standard nowadays for any email provider, so just by having the server name as a parameter you could support my own server, not just Gmail.  Having a high quality, well reviewed smtps library sounds cool, but if it's being tied to gmail, than it's useless to me.

Also, I checked out the other smtp libraries on Hackage.  Most of them has the same kind of errors than your first version, so it's good that you fixed those.  The only one that I found that seems to be easy to use and somewhat correct: http://hackage.haskell.org/package/smtp-mail-0.1.4.3

I think instead of having two libraries you should work together with @jhickner to have smtps support in his package.  It's better to have one well maintained, high quality, well reviewed, featureful implementation than several limited ones.

About your previous comment: it's possible to delete and rename packages on Hackage, but unfortunately not for the end-user.  You should try asking on mailing lists and find some hackage admin/trustee who can help you.

Thanks for taking the time to fix the issues I've previously mentioned and asking for a new review.