title: Generic tree-data-structure visual editor
body: <p>What's a visual editor (preferably browser-based) for tree data structures?  The best answer is the editor that "just works" with the largest number of languages for tree data structures.  As an example, it should be able to explore and edit XML, JSON, and CSS code, which can all be conveniently explored and edited as trees.</p>
  
  <p>Additionally, built-in support for connecting to datasources (for example, a MongoDB) would be nice.  Something like this could even work with filesystem-like structures such as a WebDAV endpoint or the Github API.</p>