Fixed the oneSignalDidFailRegisterForRemoteNotification that was using an iOS 8 method (containsString:), causing a crash in iOS 7

Author: robertoferraz

iOS_SDK/OneSignal/OneSignal.m

@@ -1355,7 +1355,7 @@ - (void)oneSignalDidRegisterForRemoteNotifications:(UIApplication*)app deviceTok
 
 - (void)oneSignalDidFailRegisterForRemoteNotification:(UIApplication*)app error:(NSError*)err {
 
-    if(err.code == 3000 && [(NSString*)[err.userInfo objectForKey:NSLocalizedDescriptionKey] containsString:@"no valid 'aps-environment'"]) {
+    if(err.code == 3000 && [((NSString*)[err.userInfo objectForKey:NSLocalizedDescriptionKey]) rangeOfString:@"no valid 'aps-environment'"].location != NSNotFound) {
         //User did not enable push notification capability
         [OneSignal setErrorNotificationType];
         [OneSignal onesignal_Log:ONE_S_LL_ERROR message:@"'Push Notification' capability not turned on. Make sure it is enabled by going to your Project Target -> Capability."];