add(other: any): Series {
    return this._combineOp(other, (a: number, b: number) => a + b, 'add');
  }
Add another Iterable, `Series`, or number to the `Series`

pandas equivalent: [Series.add](http://pandas.pydata.org/pandas-docs/stable/generated/pandas.Series.add.html)

@param {Iterable|Series|number} other
 Value to add to the `Series`

@returns {Series}

@example
const ds = new Series([1, 2, 3], {name: 'New Series'})
ds.add(5)                           // Series([6, 7, 8], {name: 'New Series'})
ds.add(new Series([2, 3, 4]))       // Series([3, 5, 7], {name: 'New Series'})
ds.add([2, 3, 4])                   // Series([3, 5, 7], {name: 'New Series'})
ds.add(Immutable.List([2, 3, 4]))   // Series([3, 5, 7], {name: 'New Series'})