#1 Doesn't work on linux

[J-P Jokela]

When running the game:
python FarmyardRoundEmUp.py

I get the following errors:
Cannot load image: images/Farmbg.png
Couldn't open images/Farmbg.png

It seems that files in images/ have .PNG filename extension instead of the assumed .png (which makes a difference on case sensitive filesystems).

Game works after doing this (or renaming the files in some other way):
rename 's/.PNG/.png/' *.PNG