Readme typos / additional info

Hey,

This is nicely done. I've programmed an email confirmation module before, but I like yours better than mine. :)

Here are some changes to the README. I hope it's helpful.

I'm trying to use it in a Django 1.7 project so I have a pull request for that coming, and I have some other things that I hope to submit a PR for next week if I get to it.