Some caveats about this project

- It was created as a uni assignment several years ago.
  The C may make you cry.

- The uni assignment called for a far simpler program.
  Hence the feature defines and isatty magic.
  (I needed to ensure the "correct" behaviour in the automated tests,
   while still allowing interactive users to see the real program)

- I didn't want to bother learning curses, so I use raw ANSI escapes.
  This bit me in the ass, because I redraw the whole screen every time you move the cursor.
  It is slow and nigh unplayable on all but the smallest field sizes.

- The git history is almost non-existent since this predates my common usage of git.