build(meson): look for howardhinnant-date

Since the "date" library has such a general name,
it often gets renamed to "hinnant-date",
"howardhinnant-date", etc. This change enables
Meson to find the library when it is called in
either ways. This "new" name is used, for example,
in the Debian package.

ci: add conventional commits check

Conventional Commits is a specification that aims at improving commit
messages and history.

It consists of a simple canonical format for commit messages:
type(optional scope): description

Having a small list of types helps understand when a change is breaking,
when it adds a feature, where it patches something, or when it is
unrelated to the main library (build system changes, CI, tests...).

This is really useful when determing when to release and what type of
release should be made (major, minor, or patch release).

chore: check VERSION_GIT_DATE in pre-commit hook

meson: small improvements

This makes Meson use the internal Python version instead of looking for
the "python3" executable in the system.

This means that python will be more likely to be found on system where
the binary is named differently (Windows?), python3 is not required (any
version will do), and could even be faster.

[SERVER] ssl: Add the possibility for the user to set a password callback

Add unit test for #970

Moved Debian data to the `debian` branch

fix: remove extra ; in include/http.h

In order to use passphrase-protected keys.
This patch does not change the default behavior:

    server.useSSL("./cert/server.crt", "./cert/server.key");
    $> ./a.out
    Enter PEM pass phrase:
    [...]

    static int password_callback(char *buf, int size, int rwflag, void *u)
    {
        static const char *password = "foobar"; // _Please_ don't do that, that's an example
        strncpy(buf, password, size);
        return strlen(password);
    }

    server.useSSL("./cert/server.crt", "./cert/server.key", false, &password_callback);
    $> ./a.out
    Listening on 0.0.0.0:9080

Key has been generated with:

    $> openssl genrsa -aes128 -passout pass:foobar -out server.key 3072

If you intend to use this feature, please look at the recent
developments on memfd_secret[1] in order to actually store a passphrase
with relative security in memory.

[1] https://lwn.net/Articles/865256/Signed-off-by: Louis Solofrizzo <lsolofrizzo@scaleway.com>

also check for linking with libatomic

include/pistache/typeid.h: include stddef.h

Include cstddef to avoid the following build failure with gcc 11:

In file included from /tmp/instance-3/output-1/build/pistache-f2f5a50f/src/../include/pistache/async.h:10,
                 from /tmp/instance-3/output-1/build/pistache-f2f5a50f/src/../include/pistache/client.h:9,
                 from /tmp/instance-3/output-1/build/pistache-f2f5a50f/src/client/client.cc:7:
/tmp/instance-3/output-1/build/pistache-f2f5a50f/src/../include/pistache/typeid.h:26:12: error: expected type-specifier before 'size_t'
   26 |   operator size_t() const { return reinterpret_cast<size_t>(id_); }
      |            ^~~~~~

Fixes:
 - http://autobuild.buildroot.org/results/2443559df8c2357476e4cbdbebb08280cbb80a3bSigned-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>

autopkgtest: don't fail on testbed failures

autopkgtest is flaky and sometimes fails even if the code is completely
fine. When it crashes like this, it exits with code 16.

With this change
all CI runs that exit with code 16 won't be considered failures, but
will just report a warning.

For more info, see `man autopkgtest`

Move the Http client to `Pistache::Experimental`

`chmod +x .hooks/pre-commit`

Cleanups

Closes #952. To be merged after #955

Nested namespaces in serializer/rapidjson.h and client.cc, reformat all
files, add .clang-format-ignore ignoring subprojects, use angled
brackets when including gtest.h.

Huge diff because of whitespace changes

Fix serializer install and remove unneeded prefix

Fixes #950

Add support for multiple archs in autopkgtest CI

This took **a lot** of time, as autopkgtest-build-qemu has been able to
build non-x86 for less than a release (version 5.17, unreleased),
and it isn't meant to be (easly) used on Ubuntu (and unfortunately GH
Actions only support Ubuntu).

This is extremely fragile; adding a CPU core breaks something, adding a
MB of RAM breaks something, installing recommended packages breaks
something... you get it. But it works. Beautiful, isn't it?

This currently tests amd64, arm64. armhf, i386 and ppc64el. s390x seems
unsupported by autopkgtest-build-qemu.

If you're curious to see how many trials it took, have a look at this
test branch:
github.com/Tachi107/pistache/tree/actions-autopkgtest-multiarch-test

Bump prismjs from 1.23.0 to 1.24.0 in /pistache.io

Bumps [prismjs](https://github.com/PrismJS/prism) from 1.23.0 to 1.24.0.
- [Release notes](https://github.com/PrismJS/prism/releases)
- [Changelog](https://github.com/PrismJS/prism/blob/master/CHANGELOG.md)
- [Commits](https://github.com/PrismJS/prism/compare/v1.23.0...v1.24.0)

---
updated-dependencies:
- dependency-name: prismjs
  dependency-type: indirect
...
Signed-off-by: dependabot[bot] <support@github.com>

Add autopkgtest GitHub Action

This CI workflow builds and tests every commit and PR using autopkgtest.
It builds a Debian Testing image using autopkgtest-build-qemu
(autopkgtest-buildvm-ubuntu-cloud was too slow), builds the source
package and test is with autopkgtest.

I'm trying to set this up for multiple architectures (see
https://github.com/Tachi107/pistache/tree/actions-autopkgtest), but for
whatever reason Ubuntu's autopkgtest-build-qemu is unable to build
images for foreign architectures, as it fails with
"E: Unable to locate package linux-image-arm64", while it should be
downloading it from
https://packages.debian.org/testing/linux-image-arm64.

If you know how to help please let me know.

Remove --no-tests option when preparing tarballs

The option was added in Meson 0.550, but we target Meson 0.50