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/private/timer.h

@@ -29,7 +29,7 @@ public:
 
 protected:
     virtual void timerEvent( QTimerEvent * event );
-    
+
 private:
     int m_timerId;
 };