TravisCI needs update

[rjonaitis]

Since June 15th, 2021, the building on travis-ci.org is ceased. Please use travis-ci.com from now on.

@9600 TravisCI can only be set up by repository owner.

[9600]

@rjonaitis I just signed up for a paid account on travis-ci.com (it's no longer free) and it's a mess. E.g. getting errors that we need a paid plan, when another part of the UI confirms we have one. Just can't seem to get it set up. On looking into this I found posts such as:

https://www.jeffgeerling.com/blog/2020/travis-cis-new-pricing-plan-threw-wrench-my-open-source-works

Along with posts in their forums with others complaining of similar errors to the some of those I experienced.

Hence suggest we move to using GitHub actions instead. Found posts which provide an intro, e.g.:

https://developer.okta.com/blog/2020/05/18/travis-ci-to-github-actions

Also "marketplace" for actions, e.g.:

https://github.com/marketplace/actions/build-c-project

[rjonaitis]

Understood, I'll look into github actions.

[rjonaitis]

TravisCI replaced with GitHub actions 90ff379

[9600]

Many thanks!

Where do we see whether the build is successful or failing? Is there a badge we can add to README.md?

[rjonaitis]

Added badge to README.md, the status icon can also be seen near commit hash in github

[9600]

Great, thanks.

I see that all three GH Actions O/S builds seem to be successful, but AppVeyor, which we have been using up until now for Windows, is failing. Maybe we should remove this if GHA can take care of all three including Windows?

[rjonaitis]

@9600 I've fixed the failure on AppVeyor, but since we now have all O/S building with GH actions, it's redundant and can be removed. I've deleted the appveyor.yml configuration, but I don't have permissions to the repository settings to disable it completely, you'll have to do that.