Qt4ProjectManager: Do not include windows.h in qtversionmanager.

Move 64bit-binary detection into Utils library.

src/libs/utils/winutils.h

@@ -58,5 +58,8 @@ QTCREATOR_UTILS_EXPORT unsigned long winQPidToPid(const Q_PID qpid);
 
 QTCREATOR_UTILS_EXPORT bool winIs64BitSystem();
 
+// Check for a 64bit binary.
+QTCREATOR_UTILS_EXPORT bool winIs64BitBinary(const QString &binary);
+
 } // namespace Utils
 #endif // WINUTILS_H