Bug 15413: Adding colons where appropriate

Bug 15413: Adding colons where appropriate

To test:

Apply patch and go to pretty much every page on the Intranet - look out
for labels on forms etc where there should be colons but aren't. If you
see any that I've missed but I'm 99% sure I got all of them! Make sure
to click through some forms where creating a new thing involves
continuing the submission on multiple pages.

Signed-off-by: Owen Leonard <oleonard@myacpl.org>
Rebased on current master and checked all changed pages.

Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Brendan Gallagher brendan@bywatersolutions.com