Added CI and Code Coverage toolings

[mojoX911]

This adds CI (build + test) using github action.

The tests in nightly build produces coverage report which can be displayed using codecov

Action for maintainer:

• Sign up in codecov (https://about.codecov.io/)
• Install codecov extension in github. Add the repo reading permission (https://github.com/marketplace/codecov)
• Setup the codecov environment secret for actions to upload coverage report.

Rest is taken care of by the scripts.

This will create CI testing report as well as code coverage report for each PR.

[chris-belcher]

Thanks for this. I'll set it up soon.

[mojoX911]

Refactored the CI workflow.

This now contains three tasks

• Continuous Integration (CI)
• Code Coverage
• Lint Checking

CI runs are configurable to create more combinations of platform, toolchain and features. Currently it just runs on ubuntu-latest with stable and nightly toolchain using an empty default feature. I have kept the action steps generic so extending different combination is just about adding them to the matrix.

This is now ready for review.

[chris-belcher]

Sorry for not getting back to this sooner. I don't know enough about CI to review this. If you're confident it's fine would you like to set it up? I can add you as another maintainer.

[mojoX911]

No Issues. I wont mind setting it up myself. I think it will help a lot in future merging process.