We don't have an easy way to test if API is missing a Since annotation,
so mention that in the contributing guide.
Signed-off-by: Emil Velikov <emil.l.velikov@gmail.com>
Link: https://github.com/kmod-project/kmod/pull/200
Signed-off-by: Lucas De Marchi <lucas.de.marchi@gmail.com>
If you're unfamiliar with `gtk-doc` here is a [quick primer].
+When adding new API, make sure to include the `Since:` token and add a new
+api-index section in `libkmod/docs/libkmod-docs.xml`.
+
## Tools manual pages
Our manual pages are written in [scdoc] a simple [markdown-like syntax]. Please