Add the check for a stale board, and fix the initializing algorithm to
ensure a full board.
returning the map's entries() array saves a step on the front end.
The convert() function is redundant with the last change in abm, to
return a d3.map().entries() array.  Fix the update() function to comply
with the new data format (entries()).
Simplify the update() function a bit.
Addressed a bug in the move() function, and rfactoring in others.