Initial implementation of Scribe

This is not at all sophisticated yet.

Some of the things that are missing:

  * Proper layout of the board (need spacing to separate mini grids
    from each other).

  * Move restrictions: Don't allow a player to move in a super grid
    that doesn't correspond to their last move's mini-grid placement
    (unless the corresponding super-grid is full).

  * Presentation to the user of the scored glyph shapes

  * Scoring of completed mini grids

  * Scoring of the super grids for the final game

And on that last point, there needs to be an option to play either the
"majority" or "super-glyph" variation for the final scoring.