BibFormat: show/hide authors for multiple records
BibFormat: show/hide authors for multiple records

* Fixes show/hide authors JavaScript facility when displaying
  several records in HTML detailed format on the same page.
  (closes #1089)

tiborsimko/invenio-formatter,inveniosoftware/invenio-formatter,tiborsimko/invenio-formatter,inveniosoftware/invenio-formatter,inveniosoftware/invenio-formatter,tiborsimko/invenio-formatter