* Clean up of TLS detection and import
* Earthly TLS controls and cleaner build envs
Adds a --tls build parameter to switch TLS backends. This PR also adds
a "str" utility for doing more concise string manipulation in POSIX sh.
* EVG Earthly tasks for more build configurations
This refactors earthly.py for extensibility and to match the
parameterization used in Earthfile.
* Support "auto" in Earthfile
* Tweak name spacing
* More feature and package summary information
* Unused LibreSSL compat

* Redefine the handling of SASL imports

Tweak importing of libsasl2 for user requirements

Tweaks the import of libsasl2 so that at import-time we don't
*require* the pkg-config files, since the dynamic library's dep
on libsasl should be sufficient to satisfy the runtime linking.

* Add FeatureSummary
* Bump Earthly version, allow setting sasl options
* Include dependencies for finding libsasl2
* Define more Earthly tasks
* make _mongo_pick public, tweak signature of bool01
* Add Earthly target for testing against cxx-driver

Build +test-cxx-driver to run a default mongo-cxx-driver using the
local mongo-c-driver as the driver backend.

* Better Earthly target docs
* Fix SASL path finding for Windows, and use parallel Make

* An earthly.sh shim script
* Tweak find-cmake to use download.sh for downloader-agnosticism.
* A cmake.sh shim to run the managed CMake version
* Fix checks in ResSearch, since libmusl does not have res_close
* Add a simple Earthfile with a few platforms
* Add EVG Earthly tasks

* Update Poetry and requests
* Hold back PyYAML to avoid Cython errors

This fixes an issue on newer Python installs that don't have distutils handy, as well as address a dependabot PR that could not merge correctly (#1284). Also, hold back PyYAML to avoid Cython-related issues (fixed in PyYAML 6, but Shrub requires PyYAML 5)

* New config settings code and defaults.

Almost all setting values have remained the same, and most setting
handling logic has remained unmodified, but this will serve as a basis
for better configuration settings handling in the future tasks for
CDRIVER-4637.

* Aside: message() cleanup

Using `message()` without a mode argument will write the message
as a NOTICE to stderr. We want to use STATUS as the default, which goes
to stdout. Systems which colorize stderr output would seemingly-randomly
color certain lines where the mode argument was missing.

* Use new CMake in more build tasks

Several build tasks still relied on older find-cmake logic. With the
new CMake changes, a more recent CMake version is required. These
tasks and scripts have been updated to use the same logic to find
the same CMake version as is used in the main build tasks.

* Don't use Batch scripts to compile for MinGW

Batch scripting is fraught with peril and will almost never do what
one expects. Any other scripting language is preferable. Since we have
Bash available and the tools to properly convert paths, just use Bash
to do this work.

* Redundant ENABLE_SHM_COUNTERS logic
* Update the "Ask for Help" section
* No longer applicable SASL checks
* Remove ENABLE_BSON, as its purpose is confusing.
- ENABLE_BSON=ON did the same as ENABLE_BSON=AUTO
- There is no "ENABLE_BSON=OFF" since then there would be nothing to build.
- USE_SYSTEM_LIBBSON=ON replaces ENABLE_BSON=SYSTEM.
- To alleviate downstreams from needing to check versions before configuring,
  allow ENABLE_BSON=SYSTEM to be specified if USE_SYSTEM_LIBBSON=ON is also set,
  thus allowing one option pair to build both before and after this revision.
- If ENABLE_BSON=SYSTEM is set but USE_SYSTEM_LIBBSON is not TRUE, then
  downstream will want to update their scripts to build with the new
  option rather than miscompile without being noticed.
* New toolchain for the build
* Don't inject the toolchain SSL into LD_LIBRARY_PATH

The toolchain CMake is incompatible with OpenSSL 1.1.0, so having it on the
library path breaks CMake. We don't need to modify LD_LIBRARY_PATH to cause
CMake to use the OpenSSL that we want. It is sufficient to prepend the SSL root
to the CMAKE_PREFIX_PATH.

* Coverage link options are usage requirements
* More Bash, less Sh
* Don't depend on distro_id

* A basic Poetry project for managing dev scripts and tools
  Fixup several other scripts to be set -u safe since we now import that
  setting.
* Use Poetry to run Sphinx
* Change variant used for release archive
  The release archive build invokes Sphinx, and since Sphinx is now installed by
  Poetry, we require a newer Python version. make-release-archive now runs
  on Ubuntu 22.04
* abi-compliance-check needs u18
  The abi-compliance-check task assumes an external `abi-compliance-checker`
  tool is installed, but that is only true on the Ubuntu 18.04 EVG
  distros.
* Significant script refactoring:
- Split components into separate files, and provide a way to selectively
  import them from other scripts.
- Download install-poetry.py on-the-fly when it is needed, not committed
  into the repository.
- Add a download-file utility.
- python.sh/poetry.sh are importable to be reused in other scripts.
* Add notes about building docs to CONTRIBUTING
* Parallelize the HTML build
* Add a console script for EVG generation

Added full support for win32 (mingw / msvc)

This means we don't need to do a double mmap() and also means we can
handle an incomplete set up shared memory area.

This should be more readable and easier to debug. Additionally, we try
to cleanup our shared memory segment on shutdown with atexit(). If the
process exits uncleanly, we have the benefit of being able to extract
the counter information after the fact.