Switch to side-by-side view

--- a/GUI/mainw/mainw.h
+++ b/GUI/mainw/mainw.h
@@ -72,8 +72,8 @@
     void paused();
     void setVolumeUi(int volume_percent);
     void setMuteUi(bool);
-
     void enableSourceSelect(bool);
+    void setCoverSize(int);
     
 signals:
     /* Player*/