Improvement on CSS

- Styled two kind of responsive forms

> form-fluid: Fluid form for general usage
> form-fixed: Fixed width, labels on the left side + responsive version.

- Created a default JS file;
- Created CSS and JS for Hint;
- Created focus effect on fields;
- Updated CSS Reset;
- Clean up HTML on application.html;
- Created a new CSS file structure;

> Created application.css with require files
> Created a CSS variables file with some vars and mixins
> Created a CSS file for responsive styles
> Created a CSS file with general styles
> Created a CSS file with form styles
> Installed Bourbon*