CirclePicker width is calculated in a wrong way
With this setup:
```jsx
<Pane
            padding={12}
            display="flex"
            alignItems="center"
            justifyContent="center"
            flexDirection="column"
            position={Position.TOP_LEFT}
            >
            <CirclePicker
              colors={[
                "#ff3722", "#9c27b0", "#3f51b5", "#4caf50", "#ffeb3b", "#795548", "#607d8b"
                ]}
              circleSpacing={12}
              circleSize={20}
            />
          </Pane>
```
we have 
![image](https://user-images.githubusercontent.com/300067/55118231-0b9a8980-50c4-11e9-9473-d8b94c06c289.png)
If we comment CirclePicker width out:
![image](https://user-images.githubusercontent.com/300067/55118280-31279300-50c4-11e9-8a79-abd30ea1cbea.png)
we get it right:
![image](https://user-images.githubusercontent.com/300067/55118296-3c7abe80-50c4-11e9-9108-74fcd6b8a4f4.png)

Any way we could disable width calculation?
@casesandberg 