Put config_dir in resources in nbconvert handlers

CSSHTMLHeaderPreprocessor uses this to include the user's custom.css
in HTML output.

Closes gh-185

notebook/nbconvert/handlers.py

@@ -98,7 +98,8 @@ class NbconvertFileHandler(IPythonHandler):
                         "name": name[:name.rfind('.')],
                         "modified_date": (model['last_modified']
                             .strftime(text.date_format))
-                    }
+                    },
+                    "config_dir": self.application.settings['config_dir'],
                 }
             )
         except Exception as e:
@@ -132,7 +133,10 @@ class NbconvertPostHandler(IPythonHandler):
         nbnode = from_dict(model['content'])
         
         try:
-            output, resources = exporter.from_notebook_node(nbnode)
+            output, resources = exporter.from_notebook_node(nbnode, resources={
+                "metadata": {"name": name[:name.rfind('.')],},
+                "config_dir": self.application.settings['config_dir'],
+            })
         except Exception as e:
             raise web.HTTPError(500, "nbconvert failed: %s" % e)
 

notebook/notebookapp.py

@@ -207,6 +207,7 @@ class NotebookWebApplication(web.Application):
             websocket_url=ipython_app.websocket_url,
             mathjax_url=ipython_app.mathjax_url,
             config=ipython_app.config,
+            config_dir=ipython_app.config_dir,
             jinja2_env=env,
             terminals_available=False,  # Set later if terminals are available
         )