Add API's for managing bucket quota (#9379)

This PR allows setting a "hard" or "fifo" quota
restriction at the bucket level. Buckets that
have reached the FIFO quota configured, will
automatically be cleaned up in FIFO manner until
bucket usage drops to configured quota.
If a bucket is configured with a "hard" quota
ceiling, all further writes are disallowed.

cmd/globals.go

@@ -36,6 +36,7 @@ import (
 	xhttp "github.com/minio/minio/cmd/http"
 	"github.com/minio/minio/pkg/auth"
 	objectlock "github.com/minio/minio/pkg/bucket/object/lock"
+
 	"github.com/minio/minio/pkg/certs"
 	"github.com/minio/minio/pkg/event"
 	"github.com/minio/minio/pkg/pubsub"
@@ -217,6 +218,9 @@ var (
 
 	globalBucketObjectLockConfig = objectlock.NewBucketObjectLockConfig()
 
+	globalBucketQuotaSys     = NewBucketQuotaSys()
+	globalBucketStorageCache bucketStorageCache
+
 	// Disk cache drives
 	globalCacheConfig cache.Config