Added display of NSLogs

Thanks for sharing your debug widget!

I've added a feature where it will now display 'NSLog' calls inside of it after 'enableLogging' is called
![screen shot 2014-04-02 at 15 06 04](https://cloud.githubusercontent.com/assets/2040617/2592230/5b166eda-ba73-11e3-9f87-0a8ce00ad263.png)
 and thought you may like to merge it. Please review and see if its of interest.

Thanks