New components added (Danger button, Content switcher)

[alexgbv]

2. Content switcher.
   Content switchers allow users to toggle between alternate views of similar or related content. Only one content section is shown at a time.

https://www.figma.com/file/MJze0qkQ2bw0D1oelqqOUK/pv-design-system?node-id=5100%3A139