fix print css less

IPython/frontend/html/notebook/handlers.py

@@ -184,6 +184,7 @@ class AuthenticatedHandler(RequestHandler):
         """
         return self.application.read_only
 
+    @property
     def use_less(self):
 	"""Use less instead of css in templates"""
 	return self.application.use_less

IPython/frontend/html/notebook/notebookapp.py

@@ -188,6 +188,7 @@ class NotebookWebApplication(web.Application):
         self.ipython_app = ipython_app
         self.read_only = self.ipython_app.read_only
         self.config = self.ipython_app.config
+        self.use_less = self.ipython_app.use_less
         self.log = log
         self.jinja2_env = Environment(loader=FileSystemLoader(os.path.join(os.path.dirname(__file__), "templates")))