remove extra \n from tools/clean_all_examples

tools/clean_all_examples

@@ -2,7 +2,7 @@ saved_pwd_before_making=$PWD
 for file in `find example tools -name Makefile`; do
     cd $(dirname $file)
     echo
-    echo "\n[$file]"
+    echo "[$file]"
     make -s clean
     cd $saved_pwd_before_making
 done