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/renderer.h

@@ -635,7 +635,7 @@ public:
 struct wxRendererVersion
 {
     wxRendererVersion(int version_, int age_);
-    
+
     /**
         Checks if the main program is compatible with the renderer having the version
         @e ver, returns @true if it is and @false otherwise.