- fix 2136: when issuing close events for all open windows in destructor, omit the actual mainwindow we are destroying
- fix 2136: when issuing close events for all open windows in destructor, omit the actual mainwindow we are destroying

jonasfoe/COPASI,copasi/COPASI,jonasfoe/COPASI,copasi/COPASI,jonasfoe/COPASI,jonasfoe/COPASI,copasi/COPASI,copasi/COPASI,copasi/COPASI,jonasfoe/COPASI,jonasfoe/COPASI,jonasfoe/COPASI,jonasfoe/COPASI,copasi/COPASI,copasi/COPASI,copasi/COPASI,copasi/COPASI,jonasfoe/COPASI