Bug 6985 - remove kw,wrdl from the search results

Bug 6985 - remove kw,wrdl from the search results

To test:

* Apply patch
* Do a search in the OPAC, the result page should now say
  "Your search returned X results" instead of
  "Your search for "kw,wrdl:yyy" returned x results"
* Do a search that will have no results, kw,wrdl should not appear in the text.

Signed-off-by: Jared Camins-Esakov <jcamins@cpbibliography.com>
Signed-off-by: Adrien Saurat <adrien.saurat@biblibre.com>
Signed-off-by: Paul Poulain <paul.poulain@biblibre.com>