In the text MARC output format, do not output multiple times the same tag in case user specified it more than once.  (Closes task #3384.)
In the text MARC output format, do not output multiple times the same
tag in case user specified it more than once.  (Closes task #3384.)

tiborsimko/invenio,tiborsimko/invenio,inveniosoftware/invenio,inveniosoftware/invenio