code: function ExplorerFlatModel(rootPath, fetchItems, root) {
  		this.rootPath = rootPath;
  		this.fetchItems = fetchItems;
  		this.root = root;
  	}
docs: Creates a new flat explorer model.
  @name orion.explorer.ExplorerFlatModel
  @class Tree model used by orion.explorer.Explorer for flat structures
  @param {String} rootPath path to load tree table root, response should contain a list of items
  @param {Function} fetchItems A function that returns a promise that resolves to the
  items at the provided location.