Wintersmith 2.0

Wintersmith 2.0 is almost done!

It brings a bunch of really great features to wintersmith and closes a ton of issues

 * Generators (think pagination)
 * Views (optional logic between contents and templates)
 * A much faster preview server
 * Dependency graphs for contents

But it needs some testing and plugins will need a small update to work.

If you wanna help out you can check out the 2.0-dev branch and npm link it, this will give you access to the wintersmith command as if you did a npm install -g

```bash
git clone -b 2.0-dev https://github.com/jnordberg/wintersmith.git
cd wintersmith
npm link
wintersmith -V
# 2.0.0-pre
```

I will start using 2.0 for all my projects as of now and fix bugs as they crop up.