Expose parseWithApns method of OSNotificationPayload

Author: rgomezp

iOS_SDK/OneSignalSDK/Source/OneSignal.h

@@ -151,6 +151,7 @@ typedef NS_ENUM(NSUInteger, OSNotificationDisplayType) {
 
 /* iOS 10+ : Groups notifications into threads */
 @property(readonly)NSString *threadId;
++(instancetype)parseWithApns:(NSDictionary*)message;
 
 @end