Removed special casing of HTTP headers and request options

Not suggesting this is ready to be merged yet, but I'm interested in your opinion if you have a chance to take a look. Am I on the right track. For now I removed the broken test since it doesn't really make sense anymore, but of course more tests should be added. Also I should probably add a `with-all-pages` macro so the user doesn't need to modify `*all-pages*` directly.