Fix unspecified context path
call parent constructor
*8412* CrossRef empty elements fix ported to master
*8420* Fix clobbered email_log assoc_id on upgrade
consider only articles that have a DOI in CrossRef XML export
*8320* Add support for public identifiers in DOIs
*8320* Add support for public identifiers in URNs
*8418* Fix author dashboard production stage in OJS