login with tugraz

added segment with hyperlink to login with SSO of tugraz. This closes #23.

invenio_theme_tugraz/templates/invenio_theme_tugraz/accounts/login.html

@@ -18,9 +18,17 @@
         <h3 class="ui header">{{ _('Log in to account') }}</h3>
       {%- endblock form_header %}
 
-      <!--TODO:
-          Add login with shibboleth
-      -->
+
+      {%- if config.INVENIO_CONFIG_TUGRAZ_SHIBBOLETH == 'True' %}
+      <div class="ui raised segment">
+        <img src="{{ url_for('static', filename=config.INVENIO_THEME_TUGRAZ_ICON)}}" height="25px" align="left">
+              <a href="{{ url_for('sso_saml.sso', idp='idp') }}">
+                {% trans type='TU Graz' %} Log in with {{ type }}{% endtrans %}
+             </a>
+            </div>
+        <h3 align="center">— OR —</h3>
+        {%- endif %}
+        
       {%- block form_outer %}
         {%- with form = login_user_form %}
           <form action="{{ url_for_security('login') }}" method="POST"