* adding covers annotations to all tests
* clock tests
* adding unit tests
* feedback
- cleaning up ValueRecorder tests
- ints are floats, so type-hint ValueRecorder::record and remove some checks
* reorganise tests
moving tests under tests/Unit and tests/Integration, and updating namespaces
changing 'make test' to just run unit tests, and generate coverage off that
adding a 'make test-integration' to run integration tests (without coverage)
adding test-integration to 'make all'
adding a separate github action to run integration tests
* tidy 'make test'
make test is now a combination of test-unit and test-integration
* fixing 'make all'
* adding unit tests for TraceIdRatioBasedSampler
I grabbed a couple of the more unit-tests tests from the integration tests. Also starting to add some @covers
annotations to start to remove false coverage
Brett McBride