Migrate the release notes from the Wiki to the repository

[thewtex]

Archive the release notes that were previously maintained on the Wiki:

https://itk.org/Wiki/ITK/Releases

in the folder ITK/Documentation/ReleaseNotes. Convert these notes to Markdown.

In the future, we can add the notes as Markdown to the repository via pull request. Then, copy the notes to GitHub Releases, Discourse, and the ITK landing pages.

[thewtex]

@jcfr do you have any tips an conversion of the MediaWiki pages to Markdown?

[blowekamp]

Have you looked into pandoc? That was use to migrate many wiki pages for SimpleITK to Sphinx or markdown.

[thewtex]

Have you looked into pandoc?

Cool -- I will try that.

[jcfr]

Use of pandoc combined with https://github.com/jcfr/mwdoc allows to convert all release pages to markdown. Here is a notebook describing how to proceed: https://nbviewer.jupyter.org/github/jcfr/jupyter-notebooks/blob/master/19_ITK_Wiki_Release_notes.ipynb