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.

interface/wx/animate.h

@@ -206,7 +206,7 @@ public:
        Default ctor.
     */
     wxAnimation();
-    
+
     /**
         Copy ctor.
     */