title: Sonata Admin Custom list field template contains link to admin edit object
body: <p>I have an admin class of an object of class Car. This object is in relation with Person or Organisation.</p>
  
  <p>I know how to add a column for Person and Organisation, and i have a link to the edit object </p>
  
  <pre><code>$listMapper
  -&gt;add('person', null, array('admin_code' =&gt; 'appli.admin.person'))
  -&gt;add('factory', null, array('admin_code' =&gt; 'appli.admin.factory'))
  </code></pre>
  
  <p>This create a link (
  
  <p>However i want just one column. I make this :     </p>
  
  <pre><code>$listMapper-&gt;add('name',null,array('label'=&gt;'Name','template'=&gt;'AcmeBundle:Admin/Car/list_name.html.twig'))
  </code></pre>
  
  <p>But in my template i want something like this but i don't understand how make the link to the edit object :</p>
  
  <pre><code>{% extends 'SonataAdminBundle:CRUD:base_list_field.html.twig' %}
  {% block field%}
  {% if object.getPerson %}
      {% set urlObject = 'linkToAdminEditPerson' %}
  {% elseif object.getFactory %}
      {% set urlObject = 'linkToAdminEditFactory' %}
  {% endif %}
  &lt;a href="{{ urlObject }}"&gt;{{ object.name }}&lt;/a&gt;
  {% endblock %}
  </code></pre>
  
  <p>Thank You</p>