Adjusted badwords to find them. Plus: make badwords run on all markdown files in the repo and update markdowns previously unchecked Closes #15898
`Curl_bufq_unwrite()` used the head instead of the tail chunk to shrink the bufq's content. Fix this and add test case that checks correct behaviour. Amended test 2601 accordingly. Reported-by: Chris Stubbs Closes #15136
For libcurl internal APIs and concepts. Closes #14552