constructor (parent, chartGroup) {
        super();

        this._size = 25;
        this._columns = [];
        this._sortBy = d => d;
        this._order = ascending;
        this._beginSlice = 0;
        this._endSlice = undefined;
        this._showSections = true;
        this._section = () => ''; // all in one section

        this._mandatoryAttributes(['dimension']);

        this.anchor(parent, chartGroup);
    }
Create a Data Table.

@param {String|node|d3.selection} parent - Any valid
{@link https://github.com/d3/d3-selection/blob/master/README.md#select d3 single selector} specifying
a dom block element such as a div; or a dom element or d3 selection.
@param {String} [chartGroup] - The name of the chart group this chart instance should be placed in.
Interaction with a chart will only trigger events and redraws within the chart's group.