Massive cleanup

[malte-v]

Things done:

• By @purefn: Added support for plain authentication
• Updated some code to work with recent versions of the networking package
• Moved everything from Web.Postie to Network.Mail.Postie (email doesn't have much to do with the web ;))
• Cleaned up remaining compiler and HLint warnings
• Formatted everything
• Added Nix support (now compiles with nixpkgs-unstable)

The new networking code seems to be working fine. I'm able to have an SMTP session with the server via telnet on both IPv4 and IPv6.

A major release on Hackage after this gets merged would be much appreciated!

[alexbiehl]

Awesome! Great work. Do you think we should remove the stupid session uuid thing as well? I always found it to be strange. Wonder how we would organize it differently but maybe you have an idea.

[alexbiehl]

Fire away!

[malte-v]

Do you think we should remove the stupid session uuid thing as well?

Not sure... What was the rationale for introducing it? I honestly don't know much about SMTP at all, I just want to receive some email so I'm probably not the best person to ask.

[malte-v]

Oh sure, it's for keeping the clients apart. I think we do need some sort of session identifier for that, so I would just leave it as is.

[malte-v]

So can you merge and release this now? :3

[alexbiehl]

What's your hackage handle?

[malte-v]

It's malvo. I don't have upload permissions yet though because the Hackage mailserver doesn't accept my email :/

[alexbiehl]

You are now a maintainer for postie on hackage. I won't be around a computer for the next two weeks.

[malte-v]

Great, thanks!