Sends a command to the client specified in AGUIDTo parameter.
function SendCmdToGUIDGroup(Cmd: TRVCmd;
AGUIDFrom, AGUIDGroup: TGUID): Integer;
Cmd is a command to send. The method frees this object itself.
AGUIDFrom must be equal to GUIDMy property of the server (unless you want to simulate a command from another client).
AGUIDGroup identifies the group of addressee. The command will be send to all members of this group.
0 if not sent; count of group members otherwise.