Lightweight API for Cloud Documents Metadata
If we want to build tools on top of the Sketch Cloud workspaces / projects & documents, we need some fast API's to get info on the Cloud hosted documents (without having to download them first).

- List of documents the user has access to
- Metadata per document:
  - Name
  - Team / Workspace
  - Project
  - ObjectID
  - Last Modified Date
  - isLibary
- Less required, but nice to have:
  - List of users currently editing
  - Preview image  