Refactor utility/decomp headers (#318)

LEGO1/mxstl/stlcompat.h

@@ -0,0 +1,18 @@
+#ifndef STLCOMPAT_H
+#define STLCOMPAT_H
+
+#include "compat.h"
+
+#if defined(_MSC_VER) && _MSC_VER <= MSVC420_VERSION
+// Disable "nonstandard extension used : 'bool'" warning spam
+#pragma warning(disable : 4237)
+#include "mxstl.h"
+#else
+#include <algorithm>
+#include <list>
+#include <set>
+using std::list;
+using std::set;
+#endif
+
+#endif // STLCOMPAT_H