added comment about new docs

--HG--
extra : convert_revision : svn%3Ab85faa78-f9eb-468e-a121-7cced6da292c%40613

scrapy/trunk/scrapy/core/exceptions.py

@@ -1,5 +1,8 @@
 """
 Scrapy core exceptions
+
+These exceptions are documented in docs/ref/exceptions.rst. Please don't add
+new exceptions here without documenting them there.
 """
 
 # Internal
@@ -44,4 +47,4 @@ class DropItem(Exception):
 
 class NotSupported(Exception):
     """Indicates a feature or method is not supported"""
-    pass
+    pass

scrapy/trunk/scrapy/core/signals.py

@@ -1,6 +1,10 @@
 """
 Scrapy core signals
+
+These signals are documented in docs/ref/signals.rst. Please don't add new
+signals here without documenting them there.
 """
+
 from pydispatch import dispatcher
 
 from scrapy import log