Fixes from testing:

Certificate files are rejected if not both files are provided
Server shuts down controlled after pressing crtl+c
Logfile location is better checked
improvements for better testing (added ids and name in templates)

cps/templates/user_edit.html

@@ -22,8 +22,6 @@
           <input type="password" class="form-control" name="password" id="password" value="" autocomplete="off">
         </div>
     {% endif %}
-
-    
     {% endif %}
     <div class="form-group">
       <label for="kindle_mail">{{_('Kindle E-Mail')}}</label>