Implement additional error handling in utils.import_object function
Merge remote-tracking branch 'upstream/master' into import-object
import_object will raise standard ImportError even in case of Value/Attribute error
correctly handle empty POST parameters
Update tornado/netutil.py

`socket.getadrrinfo` yields some strange output if Python is compiled with `--disable-ipv6`, resulting in a `bad family` error.
See http://bugs.python.org/issue16208
Add vagrant config for ubuntu 12.10.

This release is interesting because it includes a python3 port of
pycurl (which is difficult to use from tox but can at least be tested
manually).
Preliminary support for ubuntu's python3-pycurl port.
Merge pull request #670 from schlamar/patch-1

Fix bind_sockets when python is compiled with --disable-ipv6
Document --disable-ipv6 fix and only apply it when family==AF_UNSPEC.
Get twisted_test running on python 3 too.

Twisted 12.3.0 can be installed from a source checkout on python3.
Some modules, including twisted.web, are not available so skip those
tests separately.
Get the test suite passing on windows again.
Split up next.rst by module.
Note a performance improvement on PyPy in the release notes.

sys.exc_info() is very slow on pypy.  Commit
24c3d41748728cf4f3ea1509044b4abc7cea666e removed an unconditional
call to sys.exc_info when there is no error.  Performance on
demo/benchmark/benchmark.py went from 3k qps to 5k.
Use httputil.HTTPHeaders for outgoing headers in RequestHandler.

It's still a bit slower, but less than the 10% noted in the old comment.
Case sensitivity here has proven more surprising and problematic than
expected as users try to overwrite headers set by the framework.
Fix typo in next.rst.
Centralize formatting of HTTP-style dates.

Use time.strftime, which turns out to be a bit faster than either
datetime.strftime or email.utils.formatdate.
A couple of small 2.6-isms.

We can use namedtuple and the new 0o octal literal notation.
Rename future_wrap to return_future.

Allow exceptions from the initial synchronous phase to pass through
to the caller.  Add docs and tests.
Add decorator for @gen.engine-like tests.

Futures are awkward to use in stop/wait tests, and this makes it possible
to be consistent between tests and regular code.

Uses the (now-renamed) deactivate_stack_context callback
to detect when a test finishes cleanly.
Support lists of futures in @gen.engine.