change font to Roboto, change border radius, fab style to reflect google guides

Looks like there was a commit that changed everything to 'Roboto Condensed' recently, but if you look at the guidelines, https://www.google.com/design/spec/material-design/introduction.html mostly the font is Roboto. I have added a condensed h5 and h6, which seemed to be visible in some of the examples. 

I also changed the border radius to reflect the google guides, to 2px instead of 4px, and slightly altered the btn-fab style to have a subtle hover 'float' effect. Great repo, happy to have it!