Scatter Plots Aggregate Multiple Data Points into One Point

If you have the following JSON:

```json
[
  {
    "Height": 64,
    "Weight": 190
  },{
    "Height": 68,
    "Weight": 195
  },{
    "Height": 69,
    "Weight": 198
  },{
    "Height": 70,
    "Weight": 205
  },{
    "Height": 67,
    "Weight": 198
  },{
    "Height": 76,
    "Weight": 195
  }
]
```

And you use the `scatter-plot` directive:

```
<graph data="scatterData" width="100%" height="600px">
  <x field="Height" type="Measure"></x>
  <y field="Weight" type="Measure"></y>
  <scatter-plot series="Weight"></scatter-plot>
</graph>
```

The two data points where weight is 198 will aggregate into one point on the scatter plot. This is not desired behavior...