I understand that there is some need to edit the configuration of openhab2 not only by text files but also by some Web UI. This is what the PaperUI tackles in a first approach.
From my experience the major pain of editing the config-files is not the text itselt. It’s merely the need of a separate special IDE that supports editing assistance and copying of files from the developer’s machine to/from the openhab server. That’s quite annoying for beginners.
What about making the config files editable from with the web UI? A simple text widget would not be so difficult to implement. Even the full-blow-feature set of the advanced Xtext editors could be bundled in the openhab web server, see
http://spoenemann.blogspot.de/2015/05/editing-dsls-in-web-browser.html
Since Xtext 2.9 they support web editing. This would be cool