A third party plugin we use to produce an accessible date picker.
The datepicker component is based off the popular plugin Pikaday, it was chosen because it passed accessibility, performance, and quality tests. Therefore the pikaday.js file and pikaday.css file is necessary to use this component out of the box before customizing for your own use. Pikaday is also generally flexible enough with a strong API to accomplish most goals of any datepicker you might encounter.
You can view full documentation for this component in the pickaday repository. This documentation should be enough to get you going.
npm install pikaday --save