IE 11 is giving me a hard time...

I'm trying to send some binary data as a `Uint8Array` in a POST request, but `[Object object]` gets sent instead. In IE's dev tools, inspecting the request body reveals that the `Uint8Array` is being transformed incorrectly as `[Object object]`:

![screen shot 2016-03-15 at 9 31 20 am](https://cloud.githubusercontent.com/assets/440299/13793569/b991e3ea-eab4-11e5-9901-f9adee6f1beb.png)

I tried commenting out some code to see if the request will send the correct data, and it does. I commented out these lines:

```
if (utils.isArrayBuffer(requestData)) {
  requestData = new DataView(requestData);
}
```

https://github.com/mzabriskie/axios/blob/master/lib/adapters/xhr.js#L162

... and the resulting request sent binary data as expected:

<img width="463" alt="screen shot 2016-03-15 at 7 14 07 pm" src="https://cloud.githubusercontent.com/assets/440299/13800038/27c28680-eae2-11e5-9718-512fcc078cd7.png">

What is the purpose of the `new DataView()` call? What is happening that turns the binary data into the `[Object object]` string? Why does this break only in IE 11 (works in Chrome, Firefox, Edge)?

lib/adapters/xhr.js
loadEvent = 'onload';
    xDomain = true;
  }
  
  if (config.auth) {
    var username = config.auth.username || '';
    var password = config.auth.password || '';
    requestHeaders.Authorization = 'Basic ' + btoa(username + ':' + password);
  }
  request.open(config.method.toUpperCase(), buildURL(config.url, config.params, config.paramsSerializer), true);
  
  request.timeout = config.timeout;
  
  request.onprogress = function handleProgress() {};
  request.ontimeout = function handleTimeout() {};
  
  request[loadEvent] = function handleLoad() {
    if (!request || (request.readyState !== 4 && !xDomain)) {
      return;
    }
    
    
    if (request.status === 0) {
      return;
    }
    
    var responseHeaders = 'getAllResponseHeaders' in request ? parseHeaders(request.getAllResponseHeaders()) : null;
    var responseData = !config.responseType || config.responseType === 'text' ? request.responseText : request.response;
    var response = {
      data: transformData(