link handbook from footer

Author: BobHarper1

prefix_finder/frontend/templates/footer.html

@@ -6,6 +6,7 @@
     {% trans "The code for this site is available on Github" %}: <a href="https://github.com/OpenDataServices/org-ids/">{%trans "org-ids" %}</a>.
     {% trans "Licence" %}: <a href="https://www.gnu.org/licenses/agpl-3.0.html">{% trans "AGPLv3" %}</a>.
     {% trans "Report/View issues" %}: <a href="https://github.com/OpenDataServices/org-ids/issues">{% trans "org-id issues" %}</a>.
+    {% trans "To contribute lists" %}: <a href="http://docs.org-id.guide/en/latest">{% trans "contributors handbook" %}</a>.
     <a href="{% url 'terms' %}">{% trans "Terms &amp; Conditions" %}</a>.
     {% blocktrans %}Running version {% endblocktrans %}<a href="https://github.com/OpenDataServices/org-ids/tree/{{ request.tag }}">{{ request.tag }}</a>.
   </p>