[Qgis-community-team] Move old core plugins documentation and port it to Processing

[matteo]

Hi Harrissou,

> See https://github.com/qgis/QGIS-Documentation/pull/1806, the eldest open pull request. I never merged it because i expected that there are some details a doc writer would like to reuse one day. The day has come?

I missed this PR ;).

I'll say yes, the day has come so when can compact the documentation and
avoid redundancy. As I said I'll include the existing examples in the
new documentation

When I'm ready with this Processing chapter I'll make a PR that removes
also those sections

> Here, I disagree with you:
> - duplicates should be avoided. When algs get updates, it just double the work if the committer does not forget one of the page (in which case you end up with two different descriptions -really bad). Better take advantage of cross link rather than duplicating contents. 
> - GdalTools (Raster menu) is not different from fTools (Vector menu), hence they should be handled the same way. While vector has been placed at the top of Processing chapter (http://docs.qgis.org/testing/en/docs/user_manual/processing/index.html%E2%80%A6) I don't feel it makes sense there and had opened an issue report at https://github.com/qgis/QGIS-Documentation/issues/2123. Inputs are welcome. 

Ok no strong opinion and I understand all you points.

Where to place the ftools and gdaltool could be tricky. I agree that
having them at the top of Processing is not the correct place.. no ideas
for the moment

Thanks

Matteo