PropertyHandle :: UnlockSetUpdate - Unlock collection locked for update
This function allows unlocking a collection handle referenced in a collection property handle that has been locked (-> LockSetUpdate ()) within the application.
The function returns NO when the collection has been unlocked successfully. It returns an error ( YES ) when the collection has not been locked, when no instance is selected in the upper property handle (when existing) or when another error occurred.
Return value: Success ( logical )