Fix key accel overriding menus and dialogs.

All keys were being captured before being processed by any window of the
app to check for accelerators. This meant being impossible to use any
keys for input if they were saved for an accel.

- Fix #516.

src/wx/wxvbam.cpp

@@ -821,7 +821,7 @@ void MainFrame::OnSize(wxSizeEvent& event)
 
 int MainFrame::FilterEvent(wxEvent& event)
 {
-    if (event.GetEventType() == wxEVT_KEY_DOWN)
+    if (event.GetEventType() == wxEVT_KEY_DOWN && !menus_opened && !dialog_opened)
     {
         wxKeyEvent& ke = (wxKeyEvent&)event;
         int keyCode = ke.GetKeyCode();