compile warnings, and usage improvements for VisualStudio

tests/serialization_text.cpp

@@ -110,10 +110,12 @@ TEST(SerializeText, CArraySerializesTextLength) {
     EXPECT_THAT(r1, ContainerEq(t1));
 }
 
+#ifndef NDEBUG
 TEST(SerializeText, WhenCArrayNotNullterminatedThenAssert) {
     SerializationContext ctx;
     char16_t t1[CARR_LENGTH]{u"some text"};
     //make last character not nullterminated
     t1[CARR_LENGTH-1] = 'x';
     EXPECT_DEATH(ctx.createSerializer().text<2>(t1), "");
-}
+}
+#endif