added normal looking playlist icon (converted to png from wx module)

modules/gui/qt4/main_interface.cpp

@@ -173,7 +173,7 @@ void MainInterface::handleMainUi( QSettings *settings )
     ui.volMuteLabel->installEventFilter(h);
     ui.volumeSlider->setFocusPolicy( Qt::NoFocus );
 
-    BUTTON_SET_IMG( ui.playlistButton, "" ,volume-low.png,
+    BUTTON_SET_IMG( ui.playlistButton, "" , playlist_icon.png,
                         playlistEmbeddedFlag ?  qtr( "Show playlist" ) :
                                                 qtr( "Open playlist" ) );
     BUTTONACT( ui.playlistButton, playlist() );

modules/gui/qt4/res.qrc

@@ -9,5 +9,6 @@
   <file>pixmaps/volume-high.png</file>
   <file alias="vlc128.png">../../../share/vlc128x128.png</file>
   <file alias="noart.png">pixmaps/noart.png</file>
+  <file>pixmaps/playlist_icon.png</file>
  </qresource>
 </RCC>