Add test case for Lua __getitem + inheritance

Examples/test-suite/lua_inherit_getitem.i

@@ -0,0 +1,19 @@
+%module lua_inherit_getitem
+
+%inline %{
+
+class CBase {
+public:
+  const char* Foo(void) {
+    return "CBase::Foo";
+  }
+};
+
+class CDerived : public CBase {
+public:
+  void *__getitem(const char *name) const {
+    return NULL;
+  }
+};
+
+%}