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/api-datatypes.go

@@ -20,9 +20,18 @@ import (
 	"encoding/xml"
 )
 
-// ObjectIdentifier carries key name for the object to delete.
-type ObjectIdentifier struct {
+// DeletedObject objects deleted
+type DeletedObject struct {
+	DeleteMarker          bool   `xml:"DeleteMarker"`
+	DeleteMarkerVersionID string `xml:"DeleteMarkerVersionId,omitempty"`
+	ObjectName            string `xml:"Key,omitempty"`
+	VersionID             string `xml:"VersionId,omitempty"`
+}
+
+// ObjectToDelete carries key name for the object to delete.
+type ObjectToDelete struct {
 	ObjectName string `xml:"Key"`
+	VersionID  string `xml:"VersionId"`
 }
 
 // createBucketConfiguration container for bucket configuration request from client.
@@ -37,5 +46,5 @@ type DeleteObjectsRequest struct {
 	// Element to enable quiet mode for the request
 	Quiet bool
 	// List of objects to be deleted
-	Objects []ObjectIdentifier `xml:"Object"`
+	Objects []ObjectToDelete `xml:"Object"`
 }