Interconnection method should be checkboxes

- It was radio buttons before
- The hint specifies 'choose all that apply' so it should definitely be checkboxes

![screen shot 2014-10-06 at 16 33 57](https://cloud.githubusercontent.com/assets/355079/4528377/41cc2e22-4d6e-11e4-87dc-3281741d0ff5.png)
![screen shot 2014-10-06 at 16 32 26](https://cloud.githubusercontent.com/assets/355079/4528380/4532d020-4d6e-11e4-90d7-a4a34d6eb1c1.png)