[Spread] remove unused includes

- also sort includes
- also additions to precompiled header

src/Mod/Spreadsheet/App/Utils.cpp

@@ -23,15 +23,13 @@
 #include "PreCompiled.h"
 
 #ifndef _PreComp_
+# include <sstream>
 #endif
 
 #include "Utils.h"
-#include <sstream>
-#include <cstdlib>
-#include <boost/regex.hpp>
-#include <Base/Exception.h>
 #include "Sheet.h"
 
+
 /**
   * Encode \a col as a string.
   *