When disconnecting a node, clear the received buffer so that we do

not process any already received messages.

The primary reason to do this is if a node spams hundreds of messages
and we ban them, we don't want to continue processing the rest of it.

src/net.cpp

@@ -716,6 +716,7 @@ void CNode::CloseSocketDisconnect()
         printf("disconnecting node %s\n", addr.ToString().c_str());
         closesocket(hSocket);
         hSocket = INVALID_SOCKET;
+        vRecv.clear();
     }
 }