Bug 9904 - Link to plugins management should not be in global navigation

Bug 9904 - Link to plugins management should not be in global navigation

With the addition of the Plugins feature a link was added to the global
navigation in the "More" submenu. I think this is unnecessary. The
global navigation should be limited to primary Koha functons.

This patch removes the link. To test, apply the patch and confirm that
there is no longer a link to Plugins in the header navigation under
"More."

Signed-off-by: Chris Cormack <chris@bigballofwax.co.nz>
Signed-off-by: Katrin Fischer <Katrin.Fischer.83@web.de>
Template patch, works as advertised.
Signed-off-by: Jared Camins-Esakov <jcamins@cpbibliography.com>