Add useful information in the flow description

[joaquinvanschoren]

Currently, no description of flows is added in the XML that is uploaded. Please add as much useful information as possible:

• Link to MLR tutorial?
• Link to documentation of packages used (e.g. e1071 on CRAN)?
• Short textual description of the learning algorithms
• List of involved preprocessing steps with links to further documentation?
• References for further reading?
• Code snippets on how to run the flow in mlr?

You can use markdown (and even math), it will be rendered on the website: https://github.com/gollum/gollum/wiki

[giuseppec]

It is a bit ugly to extract information form help pages, but this might help:

x = XML::htmlParse(capture.output(tools:::Rd2HTML(utils:::.getHelpFile(help("mean")))))
XML::readHTMLTable(x)

• http://stackoverflow.com/questions/20121627/extracting-arguments-of-an-r-function-to-use-in-knitr
• http://stackoverflow.com/questions/1395528/scraping-html-tables-into-r-data-frames-using-the-xml-package
• https://www.r-bloggers.com/using-rvest-to-scrape-an-html-table/

[giuseppec]

This should be possible now using learnerHelp from https://github.com/mlr-org/mlr/pull/1657