Optimization of display is now done by PgLabItemDelegate. This also makes it easier in future commit
to enabled showing complete string and correctly exporting the data.
While this might seem to duplicate behaviour I believe having this code in a delegate
is a better solution.
- the logic in BaseTableModel is view logic not model logic
- letting the custom delegate determine the formatting is much more efficient
then letting the default delegate do many virtual calls to detemine how the
model wants it formatted.
