Whitespace cleanup

* remove trailing whitespace
* remove empty lines at the end of files

plugins/network/vnstat

@@ -26,7 +26,7 @@ if [ "$1" = "config" ]; then
 	echo 'totalrx.info Total data received.'
 	echo 'totalrx.cdef totalrx,1000000,*'
 	exit 0
-	
+
 fi;