[feat] Add support for image as numpy array

[qTipTip]

• Add image as array option
• Change version, and update changelog

[qTipTip]

This will solve #30, as it allows the user to first load an image using cv2 and then pass it directly to the extract_color function:

image = cv2.imread('path/to/image.png')

palette = extract_colors(image_array=image, ...)