add clock as react component

[jeremiasjutz]

This PR adds the SBB clock as a react component.
Could eventually be published as a npm package.

[kyubisation]

Hello @jeremiasjutz
This repository is no longer being maintained and we will archive it soon.
What is your motivation for wanting to contribute this code?

[jeremiasjutz]

Hi @kyubisation
I used your clock code for a project at work (a react based application) and now I'm trying to give back to the open source community in case someone else happens to need the SBB clock as a react component (because I couldn't find a official react clock component like the one you are using on beta.sbb.ch).

[kyubisation]

Thank you for reaching out 😃
Our current design system is being developed at https://github.com/lyne-design-system/lyne-components/
In the future, this will be moved to this organization. In that repository we already have an implementation of our clock and also a React wrapper for it.
Sorry for the confusion and I apologize for not being able to directly use your contribution.