Alex Bremora

I would like to split this issue into smaller ones to get a better overview of current tasks. Further, some issues are already fixed (e.g. `ca_chain` is available in `CertificateBundle`)....

I'm working on a fix. I already have a failing test. But the current implementation is a little bit weird. I think a refactoring is needed. See: [https://gist.github.com/abremora/283c733c21e952aa898ea26fb7f854a0](https://gist.github.com/abremora/283c733c21e952aa898ea26fb7f854a0)