Bugfix for HTTP upload content when running on node

lib/http-api.js

@@ -188,9 +188,10 @@ module.exports.MatrixHttpApi.prototype = {
             upload.request = this.opts.request({
                 uri: url,
                 qs: queryParams,
-                method: "POST"
+                method: "POST",
+                headers: {"Content-Type": file.type},
+                body: file.stream
             }, requestCallback(defer, callback, this.opts.onlyData));
-            file.stream.pipe(this.opts.request);
         }
 
         this.uploads.push(upload);