Image naming convention

[branrickman]

Sky.png and ground.png are the names used in the graphics folder. The difference in capitalization convention may throw off new programmers.

(Fantastic video by the way- this is the gold standard I'll be measuring other coding tutorials against from now on)

[branrickman]

Ah, you addressed it later in the video. Disregard this issue.

[rafrafek]

Capitalization is not only convention. On Linux systems it is required to match capitalization in files and code.