first version of CodeMirror based editor
there are still some inconsistencies with the rendering of brackets in combination with partial parsing, but partial parsing allows editing of large documents
Fixed rendering issues with brackets and improved time to redraw elements. Also re-added highlighting of bound elements when entering a token
no need for visitor, now it has been replaced by estraverse
Removed some files, which are not needed for the editor-version
Fixed some issues reported by jslint and made editor load sample file on start.
Removed the help-cursor which was disturbing.