refactor: remove local prism.js/css dependency

update permissions.html to reference to prism.js/css located in libs
that is installed by bower.

close issue fossasia#292

Author: juslee

open_event/static/admin/css/prism.css

@@ -3,7 +3,7 @@
 
 
 {% block body %}
-    <link href="{{url_for('static', filename='admin/css/prism.css')}}" rel="stylesheet">
+    <link href="{{url_for('static', filename='admin/lib/prism/themes/prism-okaidia.css')}}" rel="stylesheet">
     <link href="{{url_for('static', filename='admin/lib/chosen/chosen.min.css')}}" rel="stylesheet">
     <div class="col-md-2"></div>
     <div class="col-md-8">
@@ -61,7 +61,7 @@ <h2> Event Users </h2>
 {% endblock %}
 
 {% block tail %}
-<script src="{{ url_for('static', filename='admin/js/prism.js')}}"></script>
+<script src="{{ url_for('static', filename='admin/lib/prism/prism.js')}}"></script>
 <script src="{{ url_for('static', filename='admin/lib/chosen/chosen.jquery.min.js')}}"></script>
 <script language="javascript">
   (function($) {