This submodule keep the GIF encode/decode capabilities
of the Image module.
GIF is a common image storage format,
usable for a limited color palette - a GIF image can
only contain as most 256 colors - and animations.
Simple encoding:
Image.GIF.encode, Image.GIF.encode_trans
Advanced stuff:
Image.GIF.render_block, Image.GIF.header_block,
Image.GIF.end_block, Image.GIF.netscape_loop_block
Very advanced stuff:
Image.GIF._render_block, Image.GIF._gce_block