Fixes #3068 : add a popup to list dependent rules (if any) when updating a directive

When updating a directive,display first a popup with the list of dependant rules, so that the user know what are the possible impacts
The popup appears only if there are dependant rules, and the content of the popup is as below

![popup](https://f.cloud.github.com/assets/76947/8781/1f7e0f54-4486-11e2-9a57-13f22b2083fd.png)