Use different tables for different dialog columns

Use different tables for different dialog columns

Making the same table wider (in steps of 3) to get multiple columns
does not work, because it forces options to align vertically. This
wrecks dialogs like Load Engine, where one column contains a very
high option (listbox). Now differnt tables are created for each column,
packed in a new itermediate hbox. In case of the Engine Output window,
a vbox is used instead to cause vertical stacking.
  Only multi-line text-edits and listboxes are now allowed to take up
vertical space changes, while only the middle colum of the table
can take up horizontal size changes. Within packing boxes space is
equally distributed.
  The labels above the particiant-selection widgets had not the same width
as the textview / listbox, leading to misplacement of the second label.
  For Engine Settings the spontaneous breaking into columns did not
involve a SAME_ROW flag, so the 'columns' were stacked vertically.
In addition the columns were too tall for GTK. They are now 20 options max.