Fixes an unsightly empty groupbox.

As pointed out in https://github.com/TauLabs/TauLabs/pull/789, there was an empty groupbox. This PR fixes this unsightly groupbox by allowing the user to know that there is nothing to be configured.

![screen shot 2013-07-24 at 10 45 58 am](https://f.cloud.github.com/assets/1118185/847192/59d65800-f435-11e2-871e-dc50d4f6c3ad.png)