Creating and Freeing Colormaps

• pxl-col-cre-create_colormap: create_colormap/[1,2,3]
• pxl-col-cre-create_colormap_and_alloc: create_colormap_and_alloc/[1,2,3]
• pxl-col-cre-free_colormap: free_colormap/1
• pxl-col-cre-copy_colormap_and_free: copy_colormap_and_free/2