BugFix - ReturnToShelvingCart

BugFix - ReturnToShelvingCart

If the ReturnToShelvingCart syspref is on, and something needs to go in transit,
the shelving cart setting is overriding the transit.

What seems to be happening is this:
  * Item is checked in, and flagged as needing to go in transit from A to B.
  * Item is immediately flagged as shelving cart, though.  Current display says both shelving cart and in transit.
  * After the cart-to-shelf script runs, item comes out of transit and
    shows as being available at the destination library, although it hasn't
    arrived yet and no one has manually checked it in.

http://bugs.koha-community.org/show_bug.cgi?id=3701

Signed-off-by: Jonathan Druart <jonathan.druart@biblibre.com>
Signed-off-by: Paul Poulain <paul.poulain@biblibre.com>