missing CRs and modified %hostip
lib556/test556: use a real HTTP version to make test reuse more convenient
make sure the weekday in Date headers matches the date
test61: replace stray "^M" (5e 4d) at the end of a cookie with a '^M' (0d)
Gets the test working with external proxies like Privoxy again.
Closes#6463
Updated the docs to clarify and the code accordingly, with test 1528 to
verify:
When CURLHEADER_SEPARATE is set and libcurl is asked to send a request
to a proxy but it isn't CONNECT, then _both_ header lists
(CURLOPT_HTTPHEADER and CURLOPT_PROXYHEADER) will be used since the
single request is then made for both the proxy and the server.
