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/disk-cache-backend.go

@@ -60,7 +60,7 @@ type CacheChecksumInfoV1 struct {
 // Represents the cache metadata struct
 type cacheMeta struct {
 	Version string   `json:"version"`
-	Stat    statInfo `json:"stat"` // Stat of the current object `cache.json`.
+	Stat    StatInfo `json:"stat"` // Stat of the current object `cache.json`.
 
 	// checksums of blocks on disk.
 	Checksum CacheChecksumInfoV1 `json:"checksum,omitempty"`
@@ -553,7 +553,7 @@ func (c *diskCache) bitrotWriteToCache(cachePath, fileName string, reader io.Rea
 	}
 	f, err := os.Create(filePath)
 	if err != nil {
-		return 0, osErrToFSFileErr(err)
+		return 0, osErrToFileErr(err)
 	}
 	defer f.Close()