Breaking Changes:
2/10/2017: Rename of SPRKExperimentsEngine to SPRKUserFlagsManager
    Hash: 0f8bbc037637430e04e407ece94811f9310252ec
	1. SPRKExperiments group renamed to SPRKUserFlags: Remove the reference to SPRKExperiments group in xcode, and re-add SPRKUserFlags 
	2. SPRKExperimentEngine => SPRKUserFlagsManager (including .h and .m files)
	3. SPRKExperimentFlagInfo => SPRKUserFlagInfo
	4. kSPRKExperimentDefaultUnlistedFlag => kSPRKUserFlagDefaultUnlistedFlag
	5. SPRKExperimentEngine/SPRKUserFlagsManager function renames:
	   A. fetchAllExperimentDataFromServerWithCompletion => fetchAllUserFlagsFromServerWithCompletion
	   B. hasSeenIosNewsletterPromptExperimentInfo => hasSeenIosNewsletterPromptUserFlagInfo
	   C. setupSharedAndClientSpecificExperiments => setupSharedAndClientSpecificUserFlags
	6. kSPRKExperimentHasSeenIosNewsletterPromptFlag => kSPRKUserFlagHasSeenIosNewsletterPromptFlagcd .

August 2018
1. Remove SPRKNewsletterPrompt folder reference from project
2. Remove delegate function didRegisterUserNotificationSettings from AppDelegate
3. Remove setting of useLocalNotificationTriggers from SPRKAppConfig
4. Remove SPRKUserNotification folder reference from project
5. Remove from AppDelegate: - (void)application:(UIApplication *)application didReceiveRemoteNotification:(nonnull NSDictionary *)userInfo fetchCompletionHandler:(nonnull void (^)(UIBackgroundFetchResult))completionHandler
6. Remove from AppDelegate: - (void)application:(UIApplication *)application didReceiveRemoteNotification:(NSDictionary *)userInfo
7. Remove from AppDelegate: - (void)application:(UIApplication *)application handleActionWithIdentifier:(NSString *)identifier forRemoteNotification:(NSDictionary *)notification completionHandler:(void(^)())completionHandler

November 28, 2018
1. Added SPRKKeychainUtils.h/.m files, import call added to SPRKPurchaseManager. Pleas add those files to your project.
2. Enforce that the spark-ios client explicitly add the appboyTrigger events via a call to addAAToAppboyEventMappings.

March 4, 2019
1. Added SPRKPurchase/SPRKPurchaseLog.h reference to the code, please add that file reference to your projects
2. Remove calls to SPRKPurchaseManager::restorePurchasedProduct, remove loop over productStates and call SPRKPurchaseManager::restorePurchases instead

September 18, 2019
1. Required update for iOS13 forces a breaking change if the client does not update to AppboySDK 3.20+, get the latest AppboyUI/AppboyKit/SDWebImage from here: https://git.corp.adobe.com/project-marvel/appboy-ios-sdk-spark/commits/Spark_AB_3.20.1
