Fix GCC compiler warning in mono module

- thread_local.h: 'delegating constructors only available with -std=c++11 or -std=gnu++11'
- mono_reg_utils.cpp: 'extra tokens at end of #endif directive'
- mono_bottom_panel.cpp: '<fieldB> will be initialized after <fieldA> when initialized here'
- bindings_generator.cpp: 'name lookup of 'i' changed (...) matches this 'i' under ISO standard rules (...) matches this 'i' under old rules (...)'

modules/mono/utils/mono_reg_utils.cpp

@@ -228,4 +228,4 @@ cleanup:
 }
 } // namespace MonoRegUtils
 
-#endif WINDOWS_ENABLED
+#endif // WINDOWS_ENABLED