Document state of server module

[edunham]

I was looking up how to do basic IRC stuff in Rust and found my way to http://aatxe.github.io/irc/irc/server/index.html and spent an embarrassing number of minutes trying to figure out why the docs weren't displaying. Turns out there weren't supposed to be any docs. This change will prevent such confusion in anyone else who finds these docs the way I did.

[aatxe]

Good point. Sorry that this didn't already exist! Thanks!

[edunham]

Thanks, and thanks also for the quick reply! I suspect that if you outline the plan you had in mind for the server module and link to that document from #22, others might want to help out with writing it :)

Of course, I also completely understand if the overhead of triaging and reviewing a bunch of contributions would be greater than simply writing the first version yourself when you get the time.

[aatxe]

The reality is that I've mostly been putting off working on it because I can't decide on a scope, and also in much smaller part because of the mess that is Commands (see #16). I added a comment to #22 to reflect that.