Fixed semantic warnings in Xcode 4.
Added depreciated attribute to NSString+HTML -stringByStrippingTags method.
Added -stringByLinkifyingURLs method to NSString+HTML.
Check for nil values passed to NSDate+InternetDateTime methods.
NSDate+InternetDateTime now thread safe. Modernized project (Xcode 4.1).
Improved NSDate+InternetDateTime. Removed the need for GTMDefines.h.
Updated NSString HTML category to allow encoding of a string meant for displaying in a unicode document (less characters would need encoding).

Also updated the demo app to better handle errors with feeds.
Fix minor warning about comparison of integers of different signs
Merge pull request #44 from sbentzen/master

Minor change about integer sign comparison
Merged latest changes from original repo
Default compiler