code: function getPathnames(options, schema) {
    let paths = pathsFromTree(schema.tree)
    Object.keys(options['defaultHidden']).forEach(path => {
      if (paths.indexOf(path) === -1) {
        paths.push(path)
      }
    })
    return paths
  }
docs: Returns an array of pathnames based on the schema and the default settings
  
  @access private
  @param {object} options a set of options
  @param {Schema} schema a mongoose schema
  @returns {array} an array of paths