Average Color support!

This release includes:

• Average Color extracter. Spice up your app's UI with contextual colors depending on the Blurhash's average/dominant color. Get the Blurhash's average color with:

  const color = Blurhash.getAverageColor('LGFFaXYk^6#M@-5c,1J5@[or[Q6.')

  This function decodes the characters 3 to 6 ('FFaX') using the Typescript decode83 function.
• Update dependencies