Alphabet soup

It has been a loooong time since the last major release, but this one addresses one of the main problems with the component since its inception: A11y.

Thanks to the great contributions from the folks at Freshbooks in #1481, #1483 and #1484 this components is now nice to use for people using screen readers like VoiceOver or Jaws, properly announcing the selected and highlighted options.

The improvements required some changes in the aria attributes of the component which some people used for styling, hence why this could be considered a breaking change, although it will be simple upgrade for virtually everyone.