Merge branch 'core-issue-83' into 'master'

Use btn-secondary instead of btn-primary. Closes BiscuIT-ng#83.

Closes BiscuIT-ng#83

See merge request Teckids/BiscuIT/BiscuIT-App-Chronos!16

biscuit/apps/chronos/templates/chronos/edit_substitution.html

@@ -21,7 +21,7 @@
   <form method="post">
     {% csrf_token %}
     {% bootstrap_form edit_substitution_form %}
-    <button type="submit" class="btn btn-primary">
+    <button type="submit" class="btn btn-secondary">
       {% blocktrans %}Save{% endblocktrans %}
     </button>
   </form>

biscuit/apps/chronos/templates/chronos/tt_week.html

@@ -31,7 +31,7 @@
     <ul id="timetable_select_form">
       {{ select_form.as_ul }}
     </ul>
-    <button type="submit" class="btn btn-primary">
+    <button type="submit" class="btn btn-secondary">
       {% blocktrans %}Select{% endblocktrans %}
     </button>
   </form>