[Qgis-community-team] Integrating Thomas Gratier pyqgis code snippet

[matteo]

Hi writers and dev,

I'm also Ccing Thomas Gratier in this email. Thomas is the author of the
repository and related webpage:

https://github.com/webgeodatavore/pyqgis-samples
https://webgeodatavore.github.io/pyqgis-samples/

In according with Thomas, we agree that his amazing work has to be
integrated with our official documentation.

I don't know what is the way to do it:

* additional resource next to pyqgis cookbook, training manual, ecc ,
e.g. pyqgis_code_snippet?
* link to Thomas snippet within the example in the cookbook?
* other ideas?

BTW: the work of Thomas needs some updates to QGIS 2 -> QGIS 3.

With the recent Alexandre PR that enables Intersphinx and this new
entry, pyqgis doc section has superpowers ;) !

Kudos to Thomas!

Waiting for some feedbacks

Cheers

Matteo