installation: celery task entry point
installation: celery task entry point

* Fixes issue with Celery task not being registered.

Signed-off-by: Lars Holm Nielsen <7eaffca9f7cd98839b5821d0d23e09ff764b82cd@cern.ch>

inveniosoftware/invenio-accounts,inspirehep/invenio-accounts,inspirehep/invenio-accounts,inspirehep/invenio-accounts,tiborsimko/invenio-accounts,inveniosoftware/invenio-accounts,tiborsimko/invenio-accounts,tiborsimko/invenio-accounts,inveniosoftware/invenio-accounts