djangoldp_urls rewrite id(s)

To reproduce

• Get https://git.happy-dev.fr/startinblox/djangoldp-packages/djangoldp-joboffer/merge_requests/7/diffs?commit_id=912a227260cc26c512d74e7974c2ad48b79cb1be
• Remove from djangoldp_joboffer/djangoldp_urls.py

     # Dirty fix for bad id change to job-offers/self/
      url(r'^job-offers/', JobOffersViewset.urls()),

• Every @id have now the job-offers/expired/{id} url.