fix AngProj deeplinks

using the bash command line

    for f in $(git ls-files *.adoc); do sed -i s/README.md#%C3%9Cberblick/README.md#überblick/g $f; done

(anchors are case sensitive, but no URL-escaping is needed)
18 jobs for fix-angproj-url in 3 minutes and 15 seconds (queued for 8 seconds)