Trailing whitespace cleanup from files in the Code directory.

Used the following command from within the Code dir:
git ls-files *.m *.h *.json | xargs /usr/bin/sed -i '' -E 's/[[:space:]]*$//'

Code/Testing/RKTestNotificationObserver.m

@@ -95,7 +95,7 @@
             self.awaitingNotification = NO;
         }
     }
-    
+
     [self removeObserver];
 }