docs: sphinx update
docs: sphinx update

 * FIX Fixes issue with newly released Sphinx 1.4.

Signed-off-by: Orestis Melkonian <a8803610f79fcd815ba94c447e9ee72ed88af885@gmail.com>

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