Bug in 'Snake'

[d53dave]

Hi,

I was playing around with the Revised Snake and found the following bug:

When moving towards the right side and rapidly pressing the up key and then the left key causes a "Game Over".

I did not look at the code too much and it's not obvious what exactly causes the bug. If I have some time on my hands later on i'll make a pull request if I am able to make a fix.