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/tooltip.h

@@ -25,7 +25,7 @@ public:
     static void SetAutoPop(long milliseconds);
         // set the delay between subsequent tooltips to appear
     static void SetReshow(long milliseconds);
-    
+
     wxToolTip(const wxString &tip);
 
     void SetTip(const wxString& tip);