Bug fixes and avoid identical sibling messages

fixes #250, #251, #252, #253 :)

New way to display messages

Messages are shorter, more formal and now displayed beyond the targeted element.

No more interaction needed to show the message, so that we can run a11y.css on touch devices.

And it simplifies Sass code, as well as CSS code :)

Spring cleaning and a wiki

Thanks to @hugogiraudel for his help, time and ideas!

Spring cleaning starring @HugoGiraudel

v3.2.0

Improved CSS files

Updated documentation

v3.0.0

3.0.0

Last technical issues

2.3.0

v2.3.0

Gulp configuration file

2.2.1

Close #183 and close #165