[DOC] doc: remove kanban_text_ellipsis description

views.rst: replace the description of js function kanban_text_ellipsis() with a warning telling it's gone and what to use instead.

doc/reference/views.rst

@@ -934,11 +934,8 @@ Javascript API
                            caching entirely
       :returns: an image URL
 
-   .. js:function:: kanban_text_ellipsis(string[, size=160])
-
-      clips text beyond the specified size and appends an ellipsis to it. Can
-      be used to display the initial part of potentially very long fields
-      (e.g. descriptions) without the risk of unwieldy cards
+   .. warning::
+   ``kanban_text_ellipsis`` has been removed in Odoo 9. CSS ``text-overflow`` should be used instead.
 
 .. _reference/views/calendar: