Switch to side-by-side view

--- a/src/qtgui/rclmain_w.h
+++ b/src/qtgui/rclmain_w.h
@@ -132,6 +132,7 @@
     virtual void onSortDataChanged(DocSeqSortSpec);
     virtual void resultCount(int);
     virtual void showQueryDetails();
+    virtual void applyStyleSheet();
 
 signals:
     void docSourceChanged(RefCntr<DocSequence>);