Add Bower, Neat and Bitters

Execute

```
bower install --save bourbon
bower install --save neat
bower install --save bitters
```

then add to your `_base.scss` file

```sass
@import "bourbon/dist/_bourbon.scss";
@import "neat/app/assets/stylesheets/_neat.scss";
@import "bitters/app/assets/stylesheets/_base.scss";
```