Add trademark hint to about page

aleksis/core/templates/core/pages/about.html

@@ -3,8 +3,8 @@
 {% load i18n %}
 
 
-{% block browser_title %}{% blocktrans %}About AlekSIS{% endblocktrans %}{% endblock %}
-{% block page_title %}{% blocktrans %}AlekSIS – The Free School Information System{% endblocktrans %}{% endblock %}
+{% block browser_title %}{% blocktrans %}About AlekSIS®{% endblocktrans %}{% endblock %}
+{% block page_title %}{% blocktrans %}AlekSIS® – The Free School Information System{% endblocktrans %}{% endblock %}
 
 {% block content %}
 
@@ -15,11 +15,16 @@
           <span class="card-title">{% blocktrans %}About AlekSIS{% endblocktrans %}</span>
           <p>
             {% blocktrans %}
-              This platform is powered by AlekSIS, a web-based school information system (SIS) which can be used
+              This platform is powered by AlekSIS®, a web-based school information system (SIS) which can be used
               to manage and/or publish organisational artifacts of educational institutions. AlekSIS is free software and
               can be used by anyone.
             {% endblocktrans %}
           </p>
+          <p>
+            {% blocktrans %}
+              AlekSIS® is a registered trademark of the AlekSIS open source project, represented by Teckids e.V.
+            {% endblocktrans %}
+          </p>
         </div>
         <div class="card-action">
           <a class="" href="https://aleksis.org/">{% trans "Website of AlekSIS" %}</a>