allow notebook names with spaces

IPython/html/notebook/handlers.py

@@ -22,6 +22,7 b' HTTPError = web.HTTPError'
 
 from ..base.handlers import IPythonHandler
 from ..utils import url_path_join
+from urllib import quote
 
 #-----------------------------------------------------------------------------
 # Handlers
@@ -50,6 +51,8 b' class NamedNotebookHandler(IPythonHandler):'
     def get(self, notebook_path):
         nbm = self.notebook_manager
         name, path = nbm.named_notebook_path(notebook_path)
+        if name != None:
+            name = quote(name)
         if path == None:
             project = self.project + '/' + name
         else:

IPython/html/tree/handlers.py

@@ -53,7 +53,7 b' class ProjectPathDashboardHandler(IPythonHandler):'
                 project=project,
                 project_component=project.split('/'),
                 notebook_path=path,
-                notebook_name=name))    
+                notebook_name=quote(name)))    
 
 
 class TreeRedirectHandler(IPythonHandler):