Add a new toctree with reference material, including:
- API docs (Doxygen)
- Kconfig options
- Devicetree bindings
Note that the toctree is rendered manually due to the limitations Sphinx
has when it comes to including relative URLs. Hardcoding absolute URLs
in toctrees is possible, but that means we'd need to update the toctree
on every release (to point to /version/ URL), and downstream users of
the documentation would have to manually patch the toctree with their
own URL. In order to make local builds work, version prefix is only
added if publish tag is provided.
Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>
b4f968cf9d