workflows: details template improvement

* Improves the `base_details.html` template to make it easier to
  customize.

* Now also passes the workflow object to the template.

Signed-off-by: Jan Aage Lavik <jan.age.lavik@cern.ch>
deposit: allow admins to enter submissions

* Allows super admins to enter ongoing user submissions.

Signed-off-by: Jan Aage Lavik <jan.age.lavik@cern.ch>