Bug 9423: Add notforloan value to issue confirmation or blocking message

Bug 9423: Add notforloan value to issue confirmation or blocking message

When trying to checkout an item that is not for loan (due to
items.notforloan value or because itemtype is not for loan), you get a
confirmation or blocking message (depending on AllowNotForLoanOverride
syspref).

This message tells "Item is normally not for loan".

This patch adds some informations :
if itemtype is not for loan, tells "Item type is normally not for loan".
if item is not for loan due to items.notforloan value, adds notforloan
description to message.

Signed-off-by: Owen Leonard <oleonard@myacpl.org>
Works as advertised: Not for loan authorized value is correctly shown.

Signed-off-by: Paul Poulain <paul.poulain@biblibre.com>
Signed-off-by: Jared Camins-Esakov <jcamins@cpbibliography.com>
Signed-off-by: Chris Cormack <chris@bigballofwax.co.nz>