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/dataform.h

@@ -20,7 +20,7 @@ public:
     wxDataFormat(const wxChar *id);
 
     void SetId( const wxChar *id );
-    
+
     bool operator==(wxDataFormatId format) const;
     bool operator!=(wxDataFormatId format) const;
     bool operator==(const wxDataFormat& format) const;