prepared Repo to use it with a local config.

added _config_local.yml to overwrite url in the local environment if you start jekyll with --config _config.yml,_config_local.yml (see developers-guide.md)
ordering of site.pages did not work as expected.
Druckfreundliche Version, die alle Kapitel enthält, hinzugefügt.

neues print.css eingefügt.
Falscher Titel
Prepare print.css to print page counter as well.
Print Version the second. Problem bei der Github Anzeige der Printversion
wrong link for printable version
Versuch 10
Merge branch 'gh-pages' of github.com:learnweb/documentation into gh-pages