simplify showscore()

- add some comments
- drop unneeded variable initialisation
- unify display of summary for different contests
- factor out display of summary line
Change display of score for ARRL SS

- Display points and mults (here section) for ARRL SS similar to other
  contests.
Refactor display algorithm for individual score lines

- define the column 'START_COL' where the display of the score should start
- use a table for defining the column number where we display the
  different score points for each band
- use two further tables to define which bands should be shown for each
  column
- rollup the display of the 6 columns into one loop using the above
  mentioned tables