Make required comment fields styled.

When a comment field is required, let's make it LOOK required, eh?

Added some new styles, and if/else statements in the template to include them as necessary. Created some super-expert SASS for it as well

![image](https://cloud.githubusercontent.com/assets/235752/3448913/4497ebba-015f-11e4-8b91-b419976fc8d9.png)

@wedaly @marcotuts