Merge Posibility pass stream jahewson#14 from original

jahewson@daa3a5e

Author: belaa007

lib/big-xml.js

@@ -15,7 +15,7 @@ function BigXmlReader(filename, recordRegEx, options) {
   options.gzip = options.gzip || false;
 
   var parser = new expat.Parser('UTF-8');
-  var stream = fs.createReadStream(filename);
+  var stream = typeof filename === "string" ? fs.createReadStream(filename) : filename;
 
   if (options.gzip) {
     var gunzip = zlib.createGunzip();