Add specs for the fn #move-legal?.
Move the fn #king-position from utilities.js
to game-service.js.
Add spec for the fn #king-position.
Refactor the fn #chessman-positions-from;
move the fn #to-2d to this file; remove the fns #chessmen-from and
#split-&-indexify.
Use g.generate-position! instead of
g.generate-position to prevent premature exceptions;
add an omitted testing-mode start marker.
Move the fn #to-2d to the file extractors.js.
Add the helper fns #in-check? and #vulnerable-positions-for.
Remove spec for the nonexistent fn #split-&-indexify.
Add specs for the fns #in-check? and
#vulnerable-positions-for.