Add pagination buttons above capsule list

Closes #6

templates/capsule/index.html.twig

@@ -45,7 +45,12 @@
         </div>
     {% endfor %}
 
-    <div class="d-flex flex-column align-items-center mt-4 mb-4">
+    <div class="d-flex flex-column align-items-center">
+
+        <div class="d-inline-flex justify-content-center col-2 p-3">
+            {{ knp_pagination_render(capsules) }}
+        </div>
+
         {% for capsule in capsules %}
         <div class="capsule-item pb-4 col-12 col-sm-11 col-md-10 col-xxl-8">
             <div class="d-flex flex-column flex-md-row justify-content-center align-items-center mt-sm-4">