Initial Release

Initialise Colour and Palette classes with a basic usage script and relevant unit tests.

Colour(R, G, B)

• RGB instance of a colour
• Hex and HSL conversions
• Useful string representation "rgb(255, 0, 0)"
• Colour manipulation methods (lighten, darken)
• Harmonious colours (complementary, analogous, triadic)

Palette(list of Colours)

• Add "Palette Scoring Metrics" (contrast, uniqueness, harmony, brightness, brightness_balance, temperature_variation, saturation_variation)
• Add other useful palette utility methods (add colour, remove colour, palette from list of hex codes, palette to list of hex codes)