Command-line scripts for making it easier to contribute to OpenGameArt

Included:

montage-icon To create one PNG file based on different zoom levels and backgrounds with one image file.

montage-music To create one OGG Vorbis file based on 10-second start segments of multiple music files.

montage-sfx To create one OGG Vorbis file based on multiple sound files.

cydark To create a down-pitched version of a voice, based on http://www.youtube.com/watch?v=5TWZb0QfJh0

cydark To create an up-and-down-pitched version of a voice, based on http://www.youtube.com/watch?v=5TWZb0QfJh0