merged slurm_dockerimage back into slurm role

roles/cobald/tasks/main.yml

@@ -1,6 +1,9 @@
 - include_vars: cobald-slurm.yml
   when: cobald_slurm | default(False)
 
+# FIXME: replace below by
+# - include_role: slurm
+#     tasks_from: dockerimage
 - file:
     path: "/container/{{item.name}}/cobald{{item.pfx|default('')}}/"
     state: directory