Feature/a11y

Hello,
As I was wondering why inuitcss use outline:none, I'm modestly allowed me to add few stuffs for accessibility, especially for ouline:none.
Please check http://www.outlinenone.com and http://www.w3.org/TR/2008/REC-WCAG20-20081211/#navigation-mechanisms-focus-visible
Regards,
Manu