Expose the functionality of private getRowData via a public method

[IvayloG]

Expose the functionality of the private api.service method getRowData via a public proxy method, so the users can have an access to the actual row data (transactions or not) if needed.

    /**
     * @hidden
     * @internal
     */
    public getRowData(rowID: any) {
        const data = this.get_all_data(this.grid.transactions.enabled);
        const index = this.get_row_index_in_data(rowID, data);
        return data[index];
    }