[Snek] [keith-packard/snek] 86bfd4: examples: Snek game wasn't ever moving

[Keith Packard]

  Branch: refs/heads/master
  Home:   https://github.com/keith-packard/snek
  Commit: 86bfd485ab8947917b4c6bf27186da2f4bb000a3
      https://github.com/keith-packard/snek/commit/86bfd485ab8947917b4c6bf27186da2f4bb000a3
  Author: Keith Packard <keithp at keithp.com>
  Date:   2019-03-03 (Sun, 03 Mar 2019)

  Changed paths:
    M examples/snek.py

  Log Message:
  -----------
  examples: Snek game wasn't ever moving

The test to see if the move was backtracking was broken.

Signed-off-by: Keith Packard <keithp at keithp.com>