[QGIS-Developer] Processing doc - sphinx - anchors

[matteo]

> Here we go.
> https://github.com/qgis/QGIS/commit/598b8a9c41e3788962778039adcc30f2912d822f
> Currently only for master, not sure if it is safe to push to
> release-3_0 right now.
> Will backport it a bit later.
> 
> Help link now looks like
> https://docs.qgis.org/3.1/uk/docs/user_manual/processing_algs/qgis/interpolation.html#qgisidwinterpolation
> 
> Hope this solves your issues.

thanks Alex, I'm testing it and it looks great.

I saw a small drawback when the provider is `native` and not `qgis`. For
the moment I'll change all the anchors to the correct provider (e.g.
`nativepackage`, `qgisimporttospatialite`). Do you think that it would
be smart to rename native to qgis automatically?

Cheers

Matteo