## Scope

- create core test files (`test`)
- setup CMake to build and install tests
- each test has its own target as well as targets for test kind, and target for all tests
- each test kind group is its own component and can be installed per component
- all tests can also be installed together
- path is automatically set for tests run with ctest on windows (unless disabled via option)
- file containing path for test dependencies can be created on windows if option is enabled
- tests can be built as a completely independent project
- user can choose which tests to build using regex option

---------

Signed-off-by: doodspav <doodspav@gmail.com>

## Scope

- make `patomic_` options all-caps
- make `patomic_test_` options all-caps, rename slightly, and remove
`test` from prefix
- make project scope variables snake-case and remove `patomic_` prefix
- prefix argument names with `ARG_`
- move all options to the relevant `OptionVariables.cmake`

---------

Signed-off-by: doodspav <doodspav@gmail.com>

The few visible changes made:
- renamed `create_test(...)` to `_create_test(...)`
- added `create_bt(...)` and `create_ut(...)`
- BTs are skipped if `patomic::patomic` isn't available and can't be
found
- UTs are skipped if `patomic_test` isn't build as a sub-project of
`patomic` (because `patomic` sets `PATOMIC_{BINARY, SOURCE}_DIR`
variables for the UTs to find the required files)
- `gmock` currently not linked because it breaks automatic test lookup
(might add later once there's a pipeline)

---------

Signed-off-by: doodspav <doodspav@gmail.com>

- created CMake presets for compiling with the following flags (on supported platforms)
  - ansi
  - coverage
  - warning
  - sanitize
- improved tests:
  - tests now reside in their own `kind` directory
  - tests in CMake now have a label corresponding to their kind (to make it easier to run just one kind of test)
  - added a new kind, System Test (ST), currently used to check that sanitisers work
- add pipeline steps that:
  - run tests on all possible platforms, both natively and with QEMU, check that all tests succeed, and display results in GitHub summary and PR
  - check that we have achieved our minimum coverage goals, and display results in GitHub summary and PR
  - check that there are no fixmes/todos in code without an open GitHub issue linked
- update option variables:
  - `PATOMIC_BUILD_TESTING` now works properly, and depends on `PROJECT_IS_TOP_LEVEL`
  - `PATOMIC_INSTALL_CMAKEDIR` is now versioned

Implemented full public API with BTs on the API and UTs on the whole existing codebase.
Currently, only the null implementation exists.

- add macro wrappers for direct and cmpxchg implementations
- implement all operations using c11 std atomics

- added logic binary tests for all operations
- improved transaction api
  - split status into exit code, exit info, and abort reason
  - added fp_tdepth
- if fp_tdepth is supported, fp_ttest must also be supported and behave
identically to fp_tdepth
- if any raw operation is supported, both fp_tbegin and fp_tcommit must
be supported too
- if any non-flag operation is supported, all flag operations must be
supported, otherwise no flag operations may be supported
  - split fp_tabort into fp_tabort_single and fp_tabort_all
  - fp_tabort_all must be supported if fp_tabort_single is supported

- add `wrapped/tsx.h` to easily create transactional operations from
`tbegin` and `tcommit`
- remove `patomic_transaction_recommended_t`
- add `patomic_transaction_exit_info_t`
- change `PATOMIC_TRANSACTION_STATUS_ABORT_REASON` and corresponding
function to omit explicit abort check
- all transaction operations now abort without retry if flag is set

- add death tests
- assert on invalid orders in patomic_create

- license under LGPL3.0+ with linking exception
- add license and copyright notice to all files (except LICENSE.txt,
README.md, CHANGELOG.md, and json files)
- add a changelog
- rename .yml files to .yaml
- add pipeline check to ensure all files contain license and copyright
notice