Support bucket versioning (#9377)

- Implement a new xl.json 2.0.0 format to support,
  this moves the entire marshaling logic to POSIX
  layer, top layer always consumes a common FileInfo
  construct which simplifies the metadata reads.
- Implement list object versions
- Migrate to siphash from crchash for new deployments
  for object placements.

Fixes #2111

cmd/http-tracer.go

@@ -114,7 +114,7 @@ func Trace(f http.HandlerFunc, logBody bool, w http.ResponseWriter, r *http.Requ
 	reqBodyRecorder = &recordRequest{Reader: r.Body, logBody: logBody, headers: reqHeaders}
 	r.Body = ioutil.NopCloser(reqBodyRecorder)
 	t.NodeName = r.Host
-	if globalIsDistXL {
+	if globalIsDistErasure {
 		t.NodeName = GetLocalPeer(globalEndpoints)
 	}
 	// strip port from the host address