Bug 18421: Add Coce to the staff intranet

Bug 18421: Add Coce to the staff intranet

TEST PLAN:
    1) Apply the patch with git-bz
    2) Run updatedatabase.pl
        2.1) Console output should confirm database modification
    3) Visit the 'Enhanced Content' tab of admin/syspref
        3.1) ressource is /cgi-bin/koha/admin/preferences.pl?tab=enhanced_content
        3.2) You should see that the previous preference, Coce, is now CoceOPAC,
             and that a new preference was added, CoceIntranet
    4) Activate CoceIntranet
    5) Do a search for a book for which you have a Coce cover
        5.1) The cover image url should now point to a provider you defined in Coce
        5.2) Your Coce log should show a query
    6) Click on the book's name to visit the detail.pl page
        6.1) The book's cover should also be provided by Coce on that page

Signed-off-by: Owen Leonard <oleonard@myacpl.org>
Signed-off-by: Alex Buckley <alexbuckley@catalyst.net.nz>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>