Python STL container method overloading fix

Fix method overloading of methods that take STL containers of different types.
Due to some error handling that was not cleared during typehecking.

Examples/test-suite/octave/li_std_containers_overload_runme.m

@@ -0,0 +1,37 @@
+# do not dump Octave core
+if exist("crash_dumps_octave_core", "builtin")
+  crash_dumps_octave_core(0);
+endif
+
+li_std_containers_overload
+
+function check(got, expected)
+  if (!strcmp(got, expected))
+    error("Failed check. '%s' != '%s'", got, expected)
+  endif
+end
+
+v = VectorX();
+check(VectorOverload(v), "vector<X>");
+
+v = VectorY();
+check(VectorOverload(v), "vector<Y>");
+
+v = VectorInt();
+check(VectorOverload(v), "vector<int>");
+
+v = VectorString();
+check(VectorOverload(v), "vector<string>");
+
+# TODO: Conversion from an Octave sequence not implemented yet
+# v = {X()};
+# check(VectorOverload(v), "vector<X>");
+
+# v = {Y()};
+# check(VectorOverload(v), "vector<Y>");
+
+# v = {1, 2, 3};
+# check(VectorOverload(v), "vector<int>");
+
+# v = {"aaa", "bbb", "ccc"};
+# check(VectorOverload(v), "vector<string>");