Set version number in branch4.0 to 4.0.2.dev1
Fix a regression in which a timeout could fire after being cancelled.

Closes #1148.
Fixed support for test generators

This fixes the problem that AsyncTestCase no longer seemed to work with test generators (as supported by Nose, http://nose.readthedocs.org/en/latest/writing_tests.html#test-generators).
Fix a regression in gzip output for StaticFileHandler.

Streaming static responses confused the gzip output transform since
it could no longer set the correct outgoing content-length.  Now
it will fall back to chunked encoding in this case.

Closes #1156.
Add missing argument max_buffer_size to TCPClient.connect in SimpleAsyncHTTPClient
Fix a subtle reference cycle that can lead to increased memory consumption.

Closes #1165.
Limit the number of connections we will accept per call to accept_handler.

This ensures that other callbacks scheduled on the IOLoop have a chance
to run.  This shows up as increased memory usage in benchmark scenarios
(since 4.0 allowed simple http transactions to be processed synchronously).
Fix an erroneous return of None in IOStream.connect.

This causes AttributeErrors in TCPClient, although I can only
reproduce this case reliably on freebsd.

Closes #1168.
Add release notes for 4.0.2.
Set version number to 4.0.2
Merge branch 'branch4.0'

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