Login to docker repo is now needed.

roles/common/tasks/main.yml

@@ -27,3 +27,10 @@
     group: root
 
 - import_tasks: docker.yml
+
+
+- name: Log into DockerHub
+  docker_login:
+    registry: registry.webhosting.rug.nl
+    username: "{{ docker_user }}"
+    password: "{{ docker_pass }}"