Merge branch 'branch4.0'

Conflicts:
	docs/releases.rst
	setup.py
	tornado/__init__.py

diff --cc docs/releases.rst
index 4dba891ac8f24f3bf83ce9fe87f37bc470d756fe,d239c3ecc7ea9780844acd9f236c85710fcae882..30d1170dd2cd9bdff8658623cad7f6bc8e1a2519
--- 1/docs/releases.rst
--- 2/docs/releases.rst
+++ b/docs/releases.rst
@@@ -4,7 -4,7 +4,8 @@@ Release note
  .. toctree::
     :maxdepth: 2
  
 +   releases/next
+    releases/v4.0.1
     releases/v4.0.0
     releases/v3.2.2
     releases/v3.2.1