Add multi select to table

[GordonSmith]

No description provided.

[GordonSmith]

Here are some suggested steps:

1. Ensure each row in the table has a uniqueID: <tr id="xxx">...</tr>
2. Add a SelectionBag to the TableWidget
3. Add a click handler similar to: https://github.com/hpcc-systems/Visualization/blob/master/src/graph/Graph.js#L496-L498 - Note: The first param being handed to the selectionBag.click will need to be a new JS Object: {_id: ROW_UNIQUE_ID}
4. Add some new styles to the CSS to highlight the select rows.

Job Done.