Move location of center cell check

For better readability, get this out the way at the top of the loop.

Signed-off-by: Wincent Colaiuta <win@wincent.com>
Apply minor indentation fix

Signed-off-by: Wincent Colaiuta <win@wincent.com>
Add fps indicator

Updated every half-second, approximately.

Signed-off-by: Wincent Colaiuta <win@wincent.com>
Use strict

Signed-off-by: Wincent Colaiuta <win@wincent.com>