BibAuthorID: ORCID support for rabbit

* Rabbit tries to match papers to profiles by ORCID, after trying to
  do so with an INSPIRE id.

* The ORCID is located in $__j fields with the prefix of 'ORCID:'.
  (PR inspirehep/invenio#135)

Signed-off-by: Artem Tsikiridis <artem.tsikiridis@cern.ch>
Reviewed-by: Samuele Kaplun <samuele.kaplun@cern.ch>
Reviewed-by: Gilles Louppe <g.louppe@gmail.com>