[QGIS-Developer] New Processing Help System summary

[matteo]

Hi all,

I'm writing here a brief summary of the current situation of the
Processing Help system.

Currently all the QGIS algorithms have been described and all the PR in
the doc repository have been merged (kudos to Harrissou for all the
reviews!).

Right now the Help button of each Processing dialog will open the
related page of the algorithm, BUT:

* if the name of the algorithm is made by only ONE word (e.g. clip,
intersection...), the help button will open the browser to also the
correct section (that is, the user will see directly th description of
the related algorithm)
* if the name of the algorithm has >1 words (e.g. split polygon with
lines, lines to polygon, ecc.) the Help button will open the correct
page (so the algorithm GROUP) but is not able to go to the correct
algorithm anchor. This is because sphinx converts "split with lines" in
"split-with-lines" while QGIS system will always cast the words
"split-with-lines" in "splitwithlines". Not a big deal, but IMHO a pity.
We are really too close to the solution.

So Processing Help system right now consists i:

* QGIS algs -> documented
* GDAL algs -> documented
* GRASS -> documented (own docs)
* Orfeo -> documented (own docs)
* SAGA -> nothing documented

Thanks to QGIS Grants to provide this chance to give a big improvement
to the Processing framework even if not in a coding way.

Cheers

Matteo