feature #4665 Add table footer block (parijke)

This PR was merged into the 3.0.x-dev branch.

Discussion
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Add table footer block

If someone wants to add a tfoot to the index page

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Commits
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b5863ad Add table footer block

src/Resources/views/crud/index.html.twig

@@ -184,6 +184,8 @@
             {% endif %}
         {% endblock table_body %}
         </tbody>
+        {% block table_footer %}
+        {% endblock table_footer %}
     </table>
 
     {% if entities|length > 0 %}