Dont report exceptions in error handler.

src/libprs500/gui2/main_window.py

@@ -24,6 +24,7 @@ class MainWindow(QMainWindow):
         QMainWindow.__init__(self, parent)
     
     def unhandled_exception(self, type, value, tb):
+        try:
             sio = StringIO.StringIO()
             traceback.print_exception(type, value, tb, file=sio)
             fe = sio.getvalue()
@@ -32,3 +33,5 @@ class MainWindow(QMainWindow):
             msg += '<p>Detailed <b>traceback</b>:<pre>'+fe+'</pre>'
             d = ConversionErrorDialog(self, 'ERROR: Unhandled exception', msg)
             d.exec_()
+        except:
+            pass