MrJoes/tornadio — pull request #41 by ecksor (2011-12-14 11:48:36+00:00)
Title: fix for cross site authentication

When using xhr transports, "cookie" may not already be in headers for preflight request.
If request needs cookies to be set/sent, that check will result in 'Access-Control-Allow-Credentials' not being set.

Also, at least in Chrome/Firefox, setting header to value of True will result in it not being detected properly and you'll get a ```Credentials flag is true, but Access-Control-Allow-Credentials is not "true"``` error. 'Access-Control-Allow-Credentials' needs to be set to 'true'

reference https://github.com/LearnBoost/socket.io-client/pull/335