title: How to center align a checkbox in handsontable?
body: <p>I am using handsontable and my code is written in typescript/aurelia. I cannot center align the checkbox column. I followed <a href="http://docs.handsontable.com/0.16.0/demo-alignment.html" rel="nofollow">this</a> link and set the className on my checkbox column to "htCenter htMiddle". On text columns this thing works but not on the checkbox column. Whereas when I use my dev tools and set the class on the <code>&lt;td&gt;</code> to "htCenter htMiddle", it works. Is there any other way to set the alignment for this checkbox column?</p>
  
  <p>Here is the code for adding the className:</p>
  
  <p><code>this.options.columns = [
                      { data: "modalValue", renderer: linkButtonRenderer, readOnly: true },
                      { data: "uri", readOnly: true },
                      { data: "isPublic", className: "htCenter htMiddle", type: "checkbox" }
                  ];
  </code></p>