* Add GULUserDefaults to GoogleUtilities.
This is a workaround for NSUserDefaults crashing when setting values
in the background in some situations on iOS 11. This uses the C API
in order to avoid an NSNotification firing (which a class eventually
tries to update the UI from the thread that set the value).
* Add missing copyright information.
* Resolve macOS issues, address feedback.
* Removed unnecessary enum value.
* Fix GULAppDelegateSwizzler so that it doesn't crash in app extensions.
* Remove custom code to check for app extension and instead depend on GULAppEnvironmentUtil.
* Import the Swizzler sources into github
* Add subspecs to GoogleUtilities podspec
* Add post install step to test Podfile to add the preprocessor flags required for testing.
* Add the swizzler tests (except the flaky GULAppDelegateSwizzlerTest) to the Xcode project
* Add the AppDelegateSwizzler internal headers to the ios test header search path
* Add license header to GULLoggerCodes.h
* Fix/Suppress warnings in the framework.
* Disable certain classes for tvOS and macOS as well fix some additional pod lib lint warnings.
* Modify imports as well as add the required preprocessor flags to the test targets.
* Run pod deintegrate.
Paul Beusterien