WebSearch: fix string.translate call
WebSearch: fix string.translate call

* Correct the use of string.translate to string.replace in order to be
  compatible with Python-2.4.  (fixes #596, addresses #551)

tiborsimko/invenio-search,tiborsimko/invenio-records,inveniosoftware/invenio-search,inveniosoftware/invenio-search,tiborsimko/invenio-records,tiborsimko/invenio-search,inveniosoftware/invenio-records,inveniosoftware/invenio-records