fix failing links

[dlech]

This fixes the kernel.org links. OpenRoberta is still failing, but they just upgraded their server, so it may or may not resolve itself.

I'm wondering if we should just stop checking links with travis altogherter since it can't seem to handle https very well.

[WasabiFan]

I'm wondering if we should just stop checking links with travis altogherter since it can't seem to handle https very well.

The CI server has caught so many broken links that I would feel pretty insecure without it. When I originally enabled link checking, I had to fix 50-100 real broken links; the hacker docks, for example, had major issues. LEGO has also been repeatedly breaking links and rarely adding proper redirects. Despite the fact that it can be a pain to special-case the HTTPS endpoints, I still think it provides significant benefit.

It would probably be a good step to reach out to Travis support and/or open an issue on the proofer library to see if there's a real solution to this.

There are, however, workarounds we can use to make this significantly better. I currently have it configured to run nightly builds of master and have been watching those as they happen to make sure that things are running smoothly. I also wrote a Ruby script that I was trying out a few months back which would only fail the build for errors in modified files, but I didn't get a chance to test it out thoroughly enough to be confident in it.

[dlech]

Reopening #155 for now...