Describe which kind of link are available per action category

Currently, depending on the category, the action link won't be evaluated in the same xway

• MAIN_TABS only uses static link to build a Rest document link
• VIEW_ACTION_LIST uses link to a template
• some other categories mixes the kind of link (EL expression, template, static link, fancy box links ...)

This can be very confusing when adding an action in a category.

So a page is needed to describe what can be done where.