The logic did not consider the WORKINGPRESS_INT and SIZE_INT
columns added in cb80ff746b687a3ad29b53d9f633cbdc6b142c71.
By some unknown magic this worked by routing everything
through the CylindersModelFiltered model.
Let's fix it and explicitly ignore these columns. Put
the test whether a column should be ignored in a function
to avoid inconsistencies should new columns be added.
Signed-off-by: Berthold Stoeger <bstoeger@mail.tuwien.ac.at>