UNIMARC XSLT enhancement

UNIMARC XSLT enhancement

Improve UNIMARC XSL for result and detail page:

  * Add fields
  * Consolidation
  * Support RTL language display using $7 UNIMARC standard
    for Arabic and Hebrew
  * Fix bug #2773 via XSL at field level, removing NSB and
    NSE characters in biblio records, and avoiding to do
    it at application level in C4::Output.pm

Note for RM: There will be some tweaking coming next week.
If I see you don't push this patch, I will resubmit a
completed version later.

Sponsored by BULAC, www.bulac.fr