code: function _expandNestedPaths(paths) {
    var expandedPaths = [];
  
    _pathsArray(paths).forEach(function (p) {
      if (p.indexOf('.') !== -1) {
        var pathsWithRoots = p.split('.').map(function (value, index, array) {
          return array.slice(0, index + 1).join('.');
        });
  
        expandedPaths = expandedPaths.concat(pathsWithRoots);
      } else {
        expandedPaths.push(p);
      }
    });
  
    return expandedPaths;
  }
docs: Expand nested path syntax to include root paths as well. Mainly used for
  notifications on key updates, so updates on nested keys will notify root
  key, and vice-versa.
  
  Ex: 'user.email' => ['user', 'user.email']
  
  @param {String|String[]} paths