Comment 2 for bug 1821950

I've pushed a branch here, adding a new YAOUS, and modifying the volcopy editor's behavior to check the setting to determine whether or not to allow items with empty call number label boxes.

https://git.evergreen-ils.org/?p=working/Evergreen.git;a=shortlog;h=refs/heads/user/khuckins/lp1821950-call-number-labels-not-required