Added new callback

Author: nsingh-branch

BranchSDK/BNCCallbacks.h

@@ -20,3 +20,4 @@ typedef void (^callbackWithStatus) (BOOL changed, NSError * _Nullable error);
 typedef void (^callbackWithList) (NSArray * _Nullable list, NSError * _Nullable error);
 typedef void (^callbackWithUrlAndSpotlightIdentifier) (NSString * _Nullable url, NSString * _Nullable spotlightIdentifier, NSError * _Nullable error);
 typedef void (^callbackWithBranchUniversalObject) (BranchUniversalObject * _Nullable universalObject, BranchLinkProperties * _Nullable linkProperties, NSError * _Nullable error);
+typedef void (^callbackWithData) (NSData * _Nullable data, NSError * _Nullable error);