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
Adding support to override, via static_url, whether the generated URLs
should include the version signature or not.
Introduce StaticFileHandler.(get_content|set_headers) which reduces the
complexity of the HTTP GET handler of static resources.
Fixed syntax error in the altered StaticFileHandler.get() method
Move retrieval of absolute path to separate method which is also in
charge of validation.
Cache the computed absolute path to the requested resource in
StaticFileHandler. The cache is cleared on_finish of each request
in order to ensure recomputation on each request.
update the statement of testing if a handler is a list or tuple
Add hooks for HTTPClient and HTTPConnection customization.
digest authentication
add check for ssl.CertificateError
websocket_connect: don't hang on HTTP errors
Set the __test__ attribute on gen_test to False.

Without this, if a nose-using project imported gen_test nose would try
to run it as a test.
tests: test for websocket_connect failure
Fix precedence of StringIO imports for LogTrapTestCase.

io.StringIO doesn't allow byte strings even on python 2, which causes
it to fail with the standard log formatter (but not tornado's "pretty
logging").

Closes #708.
Update pyuv test for latest version of pyuv and tornado-pyuv
Add an ioloop command line flag to the benchmark script.
Add future interface to FacebookGraphMixin
Merge pull request #720 from wsantos/facebook_future

Add future interface to FacebookGraphMixin