Bug 1607 - 2nd Screen issue with MixerBoard and Karaoke Window

Also Screenshot tools.  No joy for log-window, as that is created before Audacity starts up and recognises it is on the second screen.

src/LyricsWindow.cpp

@@ -130,6 +130,7 @@ LyricsWindow::LyricsWindow(AudacityProject *parent):
       wxCommandEventHandler(LyricsWindow::OnTimer),
       NULL,
       this);
+   Center();
 }
 
 LyricsWindow::~LyricsWindow()