check_colour_return_rgb
                        Checks colour variables are either RGB values,
                        hex colour codes or a recognised colour name
                        and converts to rgb (helper funct)
generate_palette        Generate a monochrome palette
hex_to_rgb              Converts Hex codes values to RGB vectors
rgb_to_hex              Converts RGB values to hex colour code
rgba_to_hex             rgba_to_hex
rgba_to_rgb             Converts RGBA to RGB (helper function)
view_palette            Easy way to view the created palette
