added param to make lollipop scale with carbs

@jebeck or @nicolashery Small change to make add param to make lollipop scale with carbs
If I might offer a completely different tact on this.  If you were to introduce a "config" object to the properties that are passed to this react component, you can make what is happening a lot more explicit.

I.e. you would move the query parameter check outside to the place that is instantiating the component rather than inside the instantiated component.  Then, you are specifying the property and the react component is completely reactive to that property.  If you want to change it, you can change the property and the react component will update.

So, the thing that creates the react component would look something like

```
<PatientData patient={...} fetchingPatientData={...} config={ bolusRatio: params.dynamicCarbs ? 0.5 : 0.35, dynamicCarbs: params.dynamicCarbs } ... >
```