Readme update - pypi and ownership clarification

[Behoston]

Hi, I found this (not exactly) package on pypi. But repository link directs to other repository here: https://github.com/georgkrause/langcodes

I've checked that georgkrause has most commit in your repository, so I assume it's fine that development is done in his repository as well as pypi releases. However I think you should explain this situation on to of readme. This situation is quite common but always with deprecation message in previous repository and reference to old repo in the new one.