Convert list of colors to pywal format.

def colors_to_dict(colors, img):
    """Convert list of colors to pywal format."""
    return {
        "wallpaper": img,
        "alpha": util.Color.alpha_num,

        "special": {
            "background": colors[0],
            "foreground": colors[15],
            "cursor": colors[15]
        },

        "colors": {
            "color0": colors[0],
            "color1": colors[1],
            "color2": colors[2],
            "color3": colors[3],
            "color4": colors[4],
            "color5": colors[5],
            "color6": colors[6],
            "color7": colors[7],
            "color8": colors[8],
            "color9": colors[9],
            "color10": colors[10],
            "color11": colors[11],
            "color12": colors[12],
            "color13": colors[13],
            "color14": colors[14],
            "color15": colors[15]
        }
    }