Added CURLOPT_HTTP09_ALLOWED and --http0.9 for this purpose.

For now, both the tool and library allow HTTP/0.9 by default.
docs/DEPRECATE.md lays out the plan for when to reverse that default: 6
months after the 7.64.0 release. The options are added already now so
that applications/scripts can start using them already now.

Fixes #2873
Closes #3383

The tool's local port command line range parser didn't check for integer
overflows and could pass "weird" data to libcurl for this option.
libcurl however, has a strict range check for the values so it rejects
anything outside of the accepted range.

Reported-by: Brian Carpenter
Closes #3242

Adds CURLOPT_DISALLOW_USERNAME_IN_URL and --disallow-username-in-url. Makes
libcurl reject URLs with a username in them.

Closes #2340

Adds CURLOPT_TLS13_CIPHERS and CURLOPT_PROXY_TLS13_CIPHERS.

curl: added --tls13-ciphers and --proxy-tls13-ciphers

Fixes #2435
Reported-by: zzq1015 on github
Closes #2607

It is enabled by default, so --no-styled-output will switch off the
detection/use of bold headers.

Closes #2538

The feature is only enabled if the output is believed to be a tty.

-J: There's some minor differences and improvements in -J handling, as
now J should work with -i and it actually creates a file first using the
initial name and then *renames* that to the one found in
Content-Disposition (if any).

-i: only shows headers for HTTP transfers now (as documented).
Previously it would also show for pieces of the transfer that were HTTP
(for example when doing FTP over a HTTP proxy).

-i: now shows trailers as well. Previously they were not shown at all.

--libcurl: the CURLOPT_HEADER is no longer set, as the header output is
now done in the header callback.

follow-up to e05ad5d

...as there's also a version 2.

Closes #2579

Add --haproxy-protocol for the command line tool

Closes #2162