As a developer, I want to work with external content organized in hierarchies via content types, so that I can integrate a wider variety of content sources.

For example:

• A file-system has hierarchical content - I should be able to map a file-system via a content type and then browse it in an app and see the folders and be able to toggle them open and closed.
• S3 supports heirarchical content.

Acceptance Criteria:

• I can read hierarchical content and present it in an app with the standard heirarchical UI (ie nested in expandable-node folder-like structures).
• I can use transformations or mappings to work with complicated hierarchical content.
• Works with light development.