Add initial tooltip implementation
Fix jshint
Revamping buttons, and adding flat buttons.
- Added flat buttons and made them the default.
- Restyled raised buttons according to Material Design spec.
- Merged FABs into the same SCSS file, for easier reuse.
- Minor bugfixes.
Merge pull request #536 from sgomes/material-sprint-button-revamp

Revamping buttons, and adding flat buttons.