Always return an error of the domain `XCDYouTubeVideoErrorDomain`
Make sure `videoIdentifier` and `languageIdentifier` are never nil
Implement NSCopying on XCDYouTubeVideo
Implement -[XCDYouTubeVideo description]
Implement XCDYouTubeVideo comparison methods
Remove e-mail from the contact paragraph
Move the XCDYouTubeVideoQuality enum into XCDYouTubeVideo.h
Document the XCDYouTubeClient class
Document XCDYouTubeKit error codes
Document the XCDYouTubeOperation protocol
Document the XCDYouTubeVideo class
Document the XCDYouTubeVideoOperation class
Deprecate XCDYouTubeVideoQualityHD1080
Simplify preferredVideoQualities code
Deprecate XCDYouTubeVideoPlayerViewControllerDidReceiveMetadataNotification
Document the XCDYouTubeVideoPlayerViewController class
Add XCDYouTubeKit.h umbrella header
Cleanup unnecessary #import
Add new XCDYouTubeErrorNoStreamAvailable error code
Add unit tests for video initialization