code: def make_drawing
        ln_arr = create_color_string.scan(/.{#{self.width}}/)
        ln_arr.each {|ln| draw_line(ln.split(""))}
      end
docs: Takes in the path to the PNG file and
   the width (in 'pixels' - equivalent to two spaces)
   Calls create_color_string to get an array of colors & split it into rows
   Then iterates over that array, calling draw_line on each row