Remove "Latest News" column

With only one item in the "Latest News" column, I don't think it's worth putting on every page. Here's what I did: 

- Make default layout full width (then, use `default` for home page & remove `home` layout)
- move Latest News into an `_include`, include it on `/` and `/about`
- Use Bootstrap built-ins to style Latest News items

One nice thing about using bootstrap built-ins is that it brings items into alignment, for example, 

before
![image](https://cloud.githubusercontent.com/assets/2231765/5060136/82ac8cfa-6cf6-11e4-9e83-4c7bbd68729c.png)

after 
![image](https://cloud.githubusercontent.com/assets/2231765/5060137/8ad2570c-6cf6-11e4-8eba-65af4375615a.png)


Is this an acceptable change? I understand if you prefer not to change it!