QT: Chanegd the checkboxes to select mode In the PLC editor to radiobuttons, since only one should be activated at a time.

QT: Fixed double click. The second click is apparently not a second press event, but its own unique event.

GTK: Added a redraw timer, since GTK doesn't generate exposure/redraw events every 1 ms like QT does.

QT: Fixed a segmentation fault that only occured if you auto-scrolled in one direction for a very long time, it eventually messed up the stack.