Bug 24446: Update ModItemTransfer for daterequested/datecancelled

Bug 24446: Update ModItemTransfer for daterequested/datecancelled

C4::Items::ModItemTransfer is used throughout the codebase and currently
it will never set the daterequested or datecancelled fields.  With the
modifications to how circulation deals with transfers we need to update
this function to set those fields appropriately. Functionality has been
retained, ModItemTransfer will continue to add a transfer regardless of
limits or current transits existing.

Signed-off-by: Kathleen Milne <kathleen.milne@cne-siar.gov.uk>
Signed-off-by: Joonas Kylmälä <joonas.kylmala@helsinki.fi>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>