Enable C++11-only Bind() unit test for MSVS 2015+ too

This might compile with even earlier MSVS versions, but it definitely
does with the recent ones, so enable the test for this compiler, even if
it still doesn't define __cplusplus to indicate C++11 conformance by
default.

tests/events/evthandler.cpp

@@ -501,7 +501,7 @@ TEST_CASE("Event::UnbindFromHandler", "[event][bind][unbind]")
 // result in compilation errors.
 // Note that this test will work only on C++11 compilers, so we test this only
 // for such compilers.
-#if __cplusplus >= 201103
+#if __cplusplus >= 201103 || wxCHECK_VISUALC_VERSION(14)
 class HandlerNonPublic : protected wxEvtHandler
 {
 public: