mbostock/d3 — pull request #592 by kitmonisit (2012-03-15 09:22:23+00:00)
Title: Add X-Requested-With: XMLHttpRequest header to xhr

I'd like to add an `XMLHttpRequest: XMLHttpRequest` header to `d3.xhr`. I'm working with the Flask web application framework, so I figured this should be handy. From the Flask docs:

> [__is_xhr__](http://flask.pocoo.org/docs/api/#flask.Request.is_xhr)
_True_ if the request was triggered via a JavaScript XMLHttpRequest. This only works with libraries that support the `X-Requested-With` header and set it to _XMLHttpRequest_. Libraries that do that are prototype, jQuery and Mochikit and probably some more.