Otherwise when call Koptconfig again option names and items will not be
drawn. And some variables' name are changed from 'value' to 'item' which
are consistent across this module now.
For now only line spaceing and word spaceing are configurable with
'F'/'Aa' commands. And device size are passed to k2pdfopt in place of
the hard-coded default width and height(via @dpavlin).