message: Don't open a window when handling poedit://
  On non-macOS platforms, handling poedit:// URI would do as directed and
  then proceed to open a new window. Don't do the latter, it's confusing
  and wrong.
diff: @@ -724,9 +724,10 @@ bool PoeditApp::OnCmdLineParsed(wxCmdLineParser& parser)
  {
  wxString poeditURI;
  if (parser.Found(CL_HANDLE_POEDIT_URI, &poeditURI))
  + {
  client.HandleCustomURI(poeditURI);
  -
  - if (parser.GetParamCount() == 0)
  + }
  + else if (parser.GetParamCount() == 0)
  {
  client.Activate();
  }
  