Pass a torrent's infohash to custom chunk stores as the `name` option

lib/torrent.js

@@ -459,7 +459,8 @@ class Torrent extends EventEmitter {
           length: file.length,
           offset: file.offset
         })),
-        length: this.length
+        length: this.length,
+        name: this.infoHash
       })
     )