Remove all trailing spaces

No real changes, just clean up sources by removing trailing spaces from
all the non-generated files.

This should hopefully avoid future commits mixing significant changes
with insignificant whitespace ones.

include/wx/qt/statusbar.h

@@ -36,7 +36,7 @@ public:
 
     QStatusBar *GetQStatusBar() const { return m_qtStatusBar; }
     QWidget *GetHandle() const;
-    
+
 protected:
     virtual void DoUpdateStatusText(int number);