Add SCSS/Compass. Increase base font size. Narrow body width.

I started trying to do some styling and found the process without SCSS pretty time consuming. And a bunch of the Foundation CSS base stuff is set as variables. So I added SCSS. Note we don't have to include all of foundation like I have here if we don't want.

Actual style change:

* Base font size is 18px up from 16px
* Body width is narrower now, but the main layout is 100% of the body width for all screens