v0.7.1

The release updates the Swift 2.2 version of the iOS SDK and includes several bug fixes and changes.

• All Services: The service URL parameter was moved from each init to a class property. To set a custom service URL parameter, set the class property instead of passing it as a parameter to the initializer. (For example: textToSpeech.serviceURL = "...".)
• Cartfile: The Cartfile was updated to explicitly specify Swift 2.2 compatible versions of the SDK's dependencies.
• Credentials: Testing credentials were moved to a .swift file for convenience.
• Language Translator: Update the default service URL for the recent release of the Language Translator service. To use an existing Language Translation service, specify a custom service URL.
• Natural Language Classifier: Updates the trained classifier id used for testing.
• Speech to Text: Added support for additional audio formats (AudioMediaType.MuLaw and AudioMediaType.Basic)
• Speech to Text: Added support for the supported_features parameter of language models, which identifies whether certain additional service features are supported with any given model.
• Speech to Text: Fix a bug where the microphone would continue recording when disconnected by the service (which also prevented the service from operating correctly when reconnecting).
• Text to Speech: Validate the status code in the response to synthesize(). This helps to produce more meaningful error messages when using incorrect credentials with the service.