Clean-up and XML handling enhancement:

- XML helper functions always return objects by winstd::com_obj or winstd::bstr reference now to ensure proper release by caller
- get_element_value()/put_element_value() can optionally return reference to the XML object if required
- WinStd macros to simplify dplhandle<> and handle<> inherited classes reused by non-copyable classes

lib/TTLS/include/Method.h

@@ -40,6 +40,8 @@ namespace eap
 {
     class method_ttls : public method_tls
     {
+        WINSTD_NONCOPYABLE(method_ttls)
+
     public:
         ///
         /// Constructs an EAP method

lib/TTLS/include/Module.h

@@ -37,6 +37,8 @@ namespace eap
 {
     class peer_ttls : public peer
     {
+        WINSTD_NONCOPYABLE(peer_ttls)
+
     public:
         ///
         /// Constructs a EAP TTLS peer module