Merge pull request AsyncHttpClient#1213 from marenzo/master

Flip NettyResponse's BodyPart ByteBuffer

Author: slandelle

client/src/main/java/org/asynchttpclient/netty/NettyResponse.java

@@ -179,6 +179,7 @@ public ByteBuffer getResponseBodyAsByteBuffer() {
         for (HttpResponseBodyPart part : bodyParts)
             target.put(part.getBodyPartBytes());
 
+        target.flip();
         return target;
     }