Branding: Horizon needs global footer override

Horizon footer is now configurable at a global level and can live
within a theme.

It was noted that the login page will usually want its own footer.

Change-Id: I61d7876b02cbff2d36b076c201847a39b0454136
Closes-bug: #1531335

doc/source/topics/customizing.rst

@@ -277,6 +277,14 @@ The logo also acts as a hyperlink. The default behavior is to redirect to
 the desired url target e.g., ``http://sample-company.com`` in
 ``local_settings.py``, the target of the hyperlink can be changed.
 
+Customizing the Footer
+======================
+
+It is possible to customize the global and login footers using a theme's
+template override.  Simply add ``_footer.html`` for a global footer
+override or ``_login_footer.html`` for the login page's footer to your
+theme's template directory.
+
 Modifying Existing Dashboards and Panels
 ========================================
 

horizon/templates/auth/login.html

@@ -8,3 +8,7 @@
 {% block content %}
   {% include 'auth/_login.html' %}
 {% endblock %}
+
+{% block footer %}
+  {% include '_login_footer.html' %}
+{% endblock %}

openstack_dashboard/templates/_footer.html

@@ -0,0 +1,3 @@
+{% comment %}
+  A simple placeholder template for custom global footer content
+{% endcomment %}

openstack_dashboard/templates/_login_footer.html

@@ -0,0 +1,3 @@
+{% comment %}
+  A simple placeholder template for custom login footer content
+{% endcomment %}

openstack_dashboard/templates/base.html

@@ -47,7 +47,9 @@
       </div>
     {% endblock %}
     <div id="footer">
-      {% block footer %}{% endblock %}
+      {% block footer %}
+        {% include "_footer.html" %}
+      {% endblock %}
     </div>
     {% block js %}
       {% include "horizon/_scripts.html" %}