title: SWT Table - Deselecting a Row after it has been selected
body: <p>When I select a row in my table, there is no way to deselect that row.  Unless there is two rows in the table.  Then I can select the other row.  Now the 2nd row is selected and the 1st row is deselected. I thought by selecting the selected row again, that would deselect the row.  But that does not seem to be the case for me.</p>
  
  <pre><code>viewer = new AplotDataTableViewer(parent, SWT.BORDER|SWT.V_SCROLL|SWT.MULTI|SWT.FULL_SELECTION);
  </code></pre>
  
  <p>I really don't want to have to create a button to deselect current selections.</p>