title: react bootstrap-table csv exporting with mimetype
body: <p>I have a react bootstrap-table with the exportCSV option set. I have been asked to add the "text/html" mimeType to the exported csv. Is there anyway to add this as an option?</p>
  
  <p>A very basic view of the table in question is:</p>
  
  <pre><code>import { BootstrapTable, TableHeaderColumn } from 'react-bootstrap-table';
  export class Table extends Component {
      constructor() {}
      render() {
          return(
              &lt;BootstrapTable data={this.tableData} exportCSV &gt;
              ... // TableColumns etc
              &lt;/BootstrapTable&gt;
          );
      }
  }
  </code></pre>