This patch also lightly refactors the conditional structure wrapping the
call to AddItem, renaming a couple variables to remove double-negatives and
abstruse logic. If SpecifyDueDate is ON, then the input box is used to pass
GlobalDueDate, allowing modification by circ staff, resulting in a default
'sticky' due date of the global due date in that mode.
Signed-off-by: Galen Charlton <galen.charlton@liblime.com>
53a0ed93db