Added support for more data types.
Added support for more data types.

1) VT_EMPTY: appears in some WSET responses;
2) VT_UI2/VT_UI4/VT_UI8: appears in some WSET responses.

FlyingOE/q_Wind,chenhq/q_Wind,NeoRuby/q_Wind,chenhq/q_Wind,NeoRuby/q_Wind,FlyingOE/q_Wind