generateImage example outdated

[samvher]

The example code for imageCreator seems outdated, it won't compile for me because PixelRGB8 expects a Word8 as input (not Int). This does work:

imageCreator :: String -> IO ()
imageCreator path = writePng path $ generateImage pixelRenderer 250 300
   where pixelRenderer x y = PixelRGB8 (fromIntegral x) (fromIntegral y) 128

For the rest it works and I like the library, thanks for the effort.

[samvher]

I created a pull request I guess that's better.