Add documentation for the public API

[aperezdc]

As of #41 we have HotDoc wired to the build system, but writing actual documentation is still pending. So let's keep this issue open until we have a good the API reference documentation in place 😉

The original description of the issue follows, for reference.

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Probably we would want to use GTK-Doc, which despite the name does not need GTK+ at all. That would allow cross-linking to the WPE WebKit API reference if needed.

Side note: there is an upstream bug to add GTK-Doc support to WPE WebKit as well.

[zdobersek]

@aperezdc wdyt about hotdoc?
https://hotdoc.github.io/index.html

[aperezdc]

HotDoc looks nice, indeed!

[thiblahute]

If you decide to go with hotdoc I can help get started (or even do it if you do not have time, it should probably not be much time at all to do!)

[aperezdc]

@thiblahute If you would be so kind to open a PR with the needed bits to get HotDoc running that would be great. No need to write all the docs, a stub is fine and we can write the actual documentation as follow-ups.

[thiblahute]

getting #9 in before would make the integration simpler, wdyt?

EDIT: It is so simple that we do not care.

[aperezdc]

While I would like using Meson, at the same time I would rather not maintain two different build systems. While Buildroot has now support for Meson, people are still using older versions which do not include it, and I am not sure what's the situation with other build systems (e.g. Yocto). For the moment it seems like sticking with CMake would be best, so let's review #41 as-is (thanks for sending the PR!).

[aperezdc]

PR #81 adds automatic deployment of built documentation to GitHub pages.