ApiGen.org domain expired last year and was bought by another party

[cconard96]

The redirect from ApiGen.github.io to apigen.org should probably be removed to keep from directing people to the current sketchy page.

[marclaporte]

[marclaporte]

apigen.org is also listed in the description here: https://github.com/ApiGen/ApiGen.github.io

And 1 hit here:
https://github.com/search?q=org%3AApiGen%20apigen.org&type=code

@jadb @JanTvrdik