New 'title' classes (replaces existing heading styles); Updated demo to reflect changes

New heading/title styles:
![image](https://cloud.githubusercontent.com/assets/706039/3475704/fddd9b2a-02f3-11e4-8910-8f7388323dd3.png)

Also, went ahead and converted demo pages to use tabsets. Feedback wanted on this change:
![demo](https://cloud.githubusercontent.com/assets/706039/3475680/a4fdc32c-02f3-11e4-886c-c9be6018ca5b.gif)