MQTT - the start has already landed

tiny-curl - also mostly landed and is a continuous work

make menuconfig - basically no interest from users, not pushing there

I'd like to see this happen.

In rough prio order

HTTP3 is now already in full progress

Downgrade redirects can be achived almost exactly like that by setting
CURLOPT_REDIR_PROTOCOLS.

The draft-ietf-httpbis-rfc6265bis-02 draft, specify a set of prefixes
and how they should affect cookie initialization, which has been
adopted by the major browsers. This adds support for the two prefixes
defined, __Host- and __Secure, and updates the testcase with the
supplied examples from the draft.

Closes #3554
Reviewed-by: Daniel Stenberg <daniel@haxx.se>

Commit 7a09b52c98ac8d840a8a9907b1a1d9a9e684bcf5 introduced support
for the draft-ietf-httpbis-cookie-alone-01 cookie draft, and while
the entry was removed from the TODO it was mistakenly left here.
Fix by removing and rewording the entry slightly.

Closes #3530
Reviewed-by: Daniel Stenberg <daniel@haxx.se>

Removed done stuff. Removed entries no longer considered for the near
term.

Closes #2028