Fix writeboard. This fixes the intro message display on first run.
Remove a bunch of settings that don't make sense any more.

Also change a few filenames to use "12.5" instead of "12.0".
Implement scoreboard loading/saving.

Also implement the -s, -i and -c flags, and put the scoreboard in a
dot file in $HOME.

This uses encoding/gob, so is not compatible with old scoreboard files.