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
RequestHander is set up to handle "OPTIONS" requests, but the
SimpleAsyncHTTPClient does not allow "OPTIONS" requests. This is a
pain when you are trying to write test cases for CORS. This simple
patch adds "OPTIONS" to the supported _SUPPORTED_METHODS in
_HTTPConnection and a test case to go along with it.
fix handling of multiple commandline args

make commandline args override config file args when multiple=True
instead of appending to config file args
pretty up --help formatting
Add `else` as possible sub-clause in `try` blocks in templates.

Add test case.
Tweak a timing-sensitive test to have fewer false failures.
Open template files in binary mode (to be decoded as utf8 later)

Text mode in python 3 uses an environment-dependent encoding, so
add a test and run it in both C and utf-8 locales.
Merge pull request #495 from alekstorm/template_try_else

Add `else` as possible sub-clause in `try` blocks in templates.
The RequestHandler.flush callback should be run even if there is no data.

Also IOStream._try_inline_read needs the same fake-callback change
as _handle_read (I can't seem to come up with a good isolated test for this,
but it's tickled by the empty-flush test).

Closes #492.
Increase verbosity for tests on travis-ci to track down a segfault on 2.6
Disable python 2.6 on travis-ci, since I don't have enough visibility
to dig into the SSL segfault.
double-checked-locking in tornado.ioloop.IOLoop.instance()
Update vagrant configs for vagrant 1.0
Pin twisted versions in the 2.2 branch to 11.1.0 since that release doesn't
pass its tests with newer versions.
Cherry-pick b151a1ee967 into branch2.2.

Original commit message:

Add a version check for the curses unicode hack so it won't break when
python 3.2.3 or 3.3 are released.

Closes #450.
Fix reponse header sanitization.
Release notes for 2.2.1
Version number bump for 2.2.1