Add arrow/util/cancel.h to PCH builds

Qt has special treatment of  the word 'signals', and  the function RegisterCancellingSignalHandler(const std::vector<int>& signals) causes compiler issues using PCH

ApplicationLibCode/pch.h

@@ -16,6 +16,11 @@
 //
 /////////////////////////////////////////////////////////////////////////////////
 
+// NOTE: This file must be included before any other Qt header files, as the keyword 'signals' is used as a parameter name in
+// RegisterCancellingSignalHandler(const std::vector<int>& signals);
+// Qt has special treatment of 'signals', and causes compiler issues using PCH
+#include <arrow/util/cancel.h>
+
 #include "cvfObject.h"
 #include "cvfVector3.h"