added open with codeanywhere badge to README file

[mojafa]

Why?

With Codeanywhere, devs and contributors can:

• Instantly launch a cloud or local IDE with remote dev environment.
• Automatically set up and configure a remote dev environments if a devcontainer.json file is present.

Benefits:

1. Faster onboarding for new contributors.
2. Consistent and ready-to-use development environments.
3. Flexibility to work in the cloud or locally.

[boring-cyborg]

Thank you for opening your first PR! 🎉 We are very happy and would like to thank you very much for your contribution. If everything checks out, we'll make sure to review the PR as soon as possible and give feedback. In the meantime, to make the reviewing process as fast as possible, you can help us by checking the following things:

• Did you follow the JSStandard coding style? - Did you comment everywhere where the necessity of a piece of code or the
  way it was implemented is not immediately obvious?
• Did you attempt to stick as much to current coding habits as possible?
  (Note that this does not apply to pieces of code where we ourselves
  obviously violated good coding practices, which unfortunately happens
  sometimes. But please indicate this in your PR so that we know what you
  rectified!)

Furthermore, make sure that the linter does not complain, which will check your code on every new commit. If the linter task fails, make sure to run yarn lint locally and check the file eslint_report.htm which will tell you precisely what went wrong.
Stay sharp, and thanks again!