Better support for multi-tab navigation

The problem
JSF Backoffice UI depends on Seam Conversation context.
Conversation ID is transmited via URL in REST links and is associated with sever side state (currentDocument, current selection ...).

As a result, when using several tabs, if they all point to the same conversation, all the tabs share the same server side state, and this becomes a mess.

The solution
There is no simple way to detect that a user choose to navigate in a new tab.

But Florent found the solution : we detect 'normal' navigation and add propagation of the conversation to the url.
In all other cases, we use the default url that should not integrate the conversationId.

<A href="nuxeo/somepage.faces" onclick="if(!event.ctrlKey){this.href='nuxeo/somepage.faces?converstaionId=0NXMAIN1'}"> Some doc </A>

Integration
This can be directly integrated inside RestDocumentLinkRenderer and RestDocumentLink.