add main routes and templates

templates/festival/new.html.twig

@@ -0,0 +1,16 @@
+{% extends 'base.html.twig' %}
+
+{% block body %}
+    <h1>Festival creation</h1>
+
+    {{ form_start(form) }}
+        {{ form_widget(form) }}
+        <input class="btn btn-primary btn-block" type="submit" value="Créer" />
+    {{ form_end(form) }}
+
+    <ul>
+        <li>
+            <a class="btn btn-primary" href="{{ path('festival_index') }}">  <i class="fa fa-arrow-left"></i>Retour à la liste</a>
+        </li>
+    </ul>
+{% endblock %}