add less flag

IPython/frontend/html/notebook/handlers.py

@@ -184,6 +184,10 b' class AuthenticatedHandler(RequestHandler):'
         """
         return self.application.read_only
 
+    def use_less(self):
+	"""Use less instead of css in templates"""
+	return self.application.use_less
+
     @property
     def ws_url(self):
         """websocket url matching the current request
@@ -296,7 +300,8 b' class NamedNotebookHandler(AuthenticatedHandler):'
             read_only=self.read_only,
             logged_in=self.logged_in,
             login_available=self.login_available,
-            mathjax_url=self.application.ipython_app.mathjax_url,))
+            mathjax_url=self.application.ipython_app.mathjax_url,
+	    use_less=self.use_less,))
 
 
 class PrintNotebookHandler(AuthenticatedHandler):

IPython/frontend/html/notebook/notebookapp.py

@@ -345,6 +345,14 b' class NotebookApp(BaseIPythonApplication):'
     read_only = Bool(False, config=True,
         help="Whether to prevent editing/execution of notebooks."
     )
+
+    use_less = Bool(False, config=True, 
+                       help="""Wether to use Browser Side less-css parsing
+                       instead of compiled css version in templates that allows 
+                       it. This is mainly convenient when working on the less 
+                       file to avoid a build step, or if user want to overwrite
+                       some of the less variables without having to recompile
+                       everything.""")
     
     webapp_settings = Dict(config=True,
             help="Supply overrides for the tornado.web.Application that the "