Fields and Autocheck

Hi Nicholas,

1/ Adding `getRepeatable` and `getStatic` on button. I had to change the `<button>` to an `<a>` to avoid the default javascript en browse view. I also added an URL attribute.

If you think it is a backward problem to change the `<button>` I can just doing it on the repeatable and static.


2/ Added a "groupedbutton", no idea if the name is the best... (buttongroup? buttons?). Well. It allow to create a group of button.


3/ Upgraded the autocheck to skip the `slug` magic field (only if `title` field exist too).

Voila.