Suppress OCUnit warnings in Xcode 6.4

SocketRocket.xcodeproj/project.pbxproj

@@ -384,7 +384,8 @@
 		F6B208241450F597009315AF /* Project object */ = {
 			isa = PBXProject;
 			attributes = {
-				LastUpgradeCheck = 0630;
+				LastTestingUpgradeCheck = 0640;
+				LastUpgradeCheck = 0640;
 			};
 			buildConfigurationList = F6B208271450F597009315AF /* Build configuration list for PBXProject "SocketRocket" */;
 			compatibilityVersion = "Xcode 3.2";