Add missing template for activity stream

app/Template/event/file_create.php

@@ -0,0 +1,11 @@
+<?= $this->user->avatar($email, $author) ?>
+
+<p class="activity-title">
+    <?= e('%s attached a new file to the task %s',
+            $this->e($author),
+            $this->url->link(t('#%d', $task['id']), 'task', 'show', array('task_id' => $task['id'], 'project_id' => $task['project_id']))
+        ) ?>
+</p>
+<p class="activity-description">
+    <em><?= $this->e($file['name']) ?></em>
+</p>