added some widgets and simplified the balloon message

1. added "Setting" button(not implemented)
2. added "Refresh" button
3. added progressbar to show the remain bytes
4. only show remain bytes in the balloon message
fix bug: report wrong "logout information"

1.added ternary state(Connected, Disconnected, Unknown)
2.Widget::updateUI() does nothing when the state is unknown
3.removed STUNet::isConnected()