Rudder

We have small disperencies between the directive and group selection in the "edit rule" page:

- directive name can be click to select / unselect,
- groups have a little +/-, name can not be click, but they can't be deselected,
- when a group is selected, the backend page goes back to top and so we don't see the group part anymore.

We propose to:

- add a little grey cross to unselect group,
- correct the fact that the backend page when a group is selected,
- change directive to make the name not clickable and add a little green plus and a little grey cross (like group).