Modal info or about for the extension

[Manvel]

Currently there are a lot of helpful resources that are poorly accessible from the CWS installation page, so it would be helpful to have that resources available in the Extension UI:

• Create an about tab or a modal linking to current resources:
  • https://github.com/Manvel/Privacy-Manager#reporting-bugs-suggestions-and-questions
  • https://github.com/Manvel/Privacy-Manager#translations
  • https://github.com/Manvel/Privacy-Manager
  • https://github.com/Manvel/Privacy-Manager/blob/master/privacy-policy.md