Implement "disabled" tooltip on grayed out documents to explain why the document is disabled

A "disabled" tooltip on grayed out documents explaining why 

The restriction can be set by nodetype so the link picker can be restricted to one or more document types, folder types or images.

Since we will show which types can be used with the field or component or as a link in rich text editor , we can use a more general tooltips saying 

• "This item cannot be used with [component name] component"
• "This item cannot be used with the field"  - this can cover link, docbase or image link fields
• "This item cannot be linked in the document" - this can cover the rich text image links and document/page links