improve internal item counter mechanisms and implement bucket quotas (#326)

- [x] Refactoring of internal counting API
- [x] Repair procedure for counters (it's an offline procedure!!!)
- [x] New counter for objects in buckets
- [x] Add quotas to buckets struct
- [x] Add CLI to manage bucket quotas
- [x] Add admin API to manage bucket quotas
- [x] Apply quotas by adding checks on put operations
- [x] Proof-read

Co-authored-by: Alex Auvolat <alex@adnab.me>
Reviewed-on: https://git.deuxfleurs.fr/Deuxfleurs/garage/pulls/326
Co-authored-by: Alex <alex@adnab.me>
Co-committed-by: Alex <alex@adnab.me>

src/api/s3/api_server.rs

@@ -212,7 +212,7 @@ impl ApiHandler for S3ApiServer {
 				.await
 			}
 			Endpoint::PutObject { key } => {
-				handle_put(garage, req, bucket_id, &key, content_sha256).await
+				handle_put(garage, req, &bucket, &key, content_sha256).await
 			}
 			Endpoint::AbortMultipartUpload { key, upload_id } => {
 				handle_abort_multipart_upload(garage, bucket_id, &key, &upload_id).await
@@ -226,7 +226,7 @@ impl ApiHandler for S3ApiServer {
 					garage,
 					req,
 					&bucket_name,
-					bucket_id,
+					&bucket,
 					&key,
 					&upload_id,
 					content_sha256,