Add new Slider component

[markteekman]

Although sliders are discouraged when building accessible applications, there can be use cases for them. Since there already exist other sliders like Swiper.js (note: I haven't tested whether their accessibility features fully comply with the WCAG standards), we're making something more specific, like a product image slider.

Notes

• TypeScript support
• Vanilla example: https://codepen.io/markteekman/pen/abPgVGO