fix #983 Error tip is now positioned relative to the invalid entry

It is now possible to position the error tool tip on any element within the <code>@aria:MultiAutoComplete</code> or any other widget that uses <code>aria.widgets.WidgetTrait</code>

To change the position of the error tip, simply use the <code>errorTipPosition</code> property of the widget.  Possible values:
```javascript
errorTipPosition : "top left"
errorTipPosition : "top right"
errorTipPosition : "bottom left"
errorTipPosition : "bottom right"
```
Here is an example with the <code>@aria:MultiAutoComplete</code> widget:

```javascript 
{@aria:MultiAutoComplete{
      label:"Choose your city: ",
      labelPos:"left",
      labelAlign:"right",
      width:400,
      block:false,
      labelWidth:180,
      resourcesHandler : getNationsHandler(1),
      spellCheck: false,
      freeText:false,      
      errorTipPosition: "top left",
      bind:{
        "value" : {
          inside : data,
          to : 'foo'
        }
      }
}/}