Display if debug app, new logging option

This PR adds some information to tell if the project has been built as a release or debug app. When the project has been properly built as a debug app it will tell you it is a Debug Version in the settings screen:

![photo 3](https://f.cloud.github.com/assets/1192780/1144866/51aef2fe-1dd9-11e3-8305-3419293d8f64.PNG)

Additionally this also adds an new logging option that will only appear when built as a debug app. When using `ULog(@"This debug message is really helpful.");` a UI Alert like follows will appear when hit:

![uuoum](https://f.cloud.github.com/assets/1192780/1144873/09b3b7ae-1dda-11e3-9986-d6646bb12006.png)

This PR was partially created to help in assisting with https://github.com/OneBusAway/onebusaway-iphone/issues/21#issuecomment-24442434.