code: function _addUniqueItems(arry, obj) {
    obj = _arrayify(obj)
    arry = _arrayify(arry)
    _each(obj, o => {
      if (arry.indexOf(o) < 0) {
        arry.push(o)
      }
    })
    return arry
  }
docs: Adds items to the arry from the obj only if it
  is not in the arry already
  @param {Array.<*>} arry
  @param {*|Array.<*>} obj
  @returns {Array.<*>} arry
  @private
  @examples
  _addUniqueItems(1, 2) // => [1,2]
  _addUniqueItems(1, [2,3]) // => [1,2,3]
  _addUniqueItems([1,2], 3) // => [1,2,3]
  _addUniqueItems([1,2], [3,4]) // => [1,2,3,4]
  _addUniqueItems([1,2], [3,1]) // => [1,2,3]
  _addUniqueItems([1,2], [1,2]) // => [1,2]
  _addUniqueItems([1,2], [1,2]) // => [1,2]
  _addUniqueItems([1,2,3], [1,2,1,2,3]) // => [1,2,3]