Fix some help

git-svn-id: https://redmine.imt-atlantique.fr/svn/xaal/code/Python/trunk@2048 b32b6428-25c9-4566-ad07-03861ab6144f

apps/tools/xaal/tools/tail.py

@@ -62,7 +62,7 @@ def usage():
     print("    level=0 => display all messages")
     print("    level=1 => hide alive messages")
     print("    level=2 => hide reply messages")
-    print("    level=3 => only display attributesChange")
+    print("    level=3 => only notifications (attributesChange)")