Add include guard due to dup name in utils.h - WIP

tests/all_tests/enum_to_int.cpp

+#ifndef INCLUDE_WATCHER_ITA_SIMULATION_SCHEDULER_UTILS
+#define INCLUDE_WATCHER_ITA_SIMULATION_SCHEDULER_UTILS
+
 #include <type_traits>
 
 template <typename Enumeration>
@@ -5,4 +8,6 @@ auto as_integer ( Enumeration const value )
 -> typename std::underlying_type<Enumeration>::type
 {
 	return static_cast< typename std::underlying_type<Enumeration>::type >( value );
-}
\ No newline at end of file
+}
+
+#endif // INCLUDE_WATCHER_ITA_SIMULATION_SCHEDULER_UTILS
\ No newline at end of file