Update TODO file

TODO

@@ -1,13 +1,5 @@
- * Make use of sparse file regions in download data for faster hashing. This is available as whence 3 and 4 on some OS?
+ * Make use of sparse file regions in download data for faster hashing. This is available as whence 3 and 4 on some OSs?
  * When we're choked and interested, are we not interested if there's no longer anything that we want?
  * dht: Randomize triedAddrs bloom filter to allow different Addr sets on each Announce.
  * data/blob: Deleting incomplete data triggers io.ErrUnexpectedEOF that isn't recovered from.
- * UL/DL rate-limiting.
- * Handle Torrent being dropped before GotInfo.
- * Track connection chunk contributions to successful and failed piece hashes. Only drop the worst performer on a bad hash. Maybe block its IP.
- * Remove assumptions that the first piece requested will be the first that peers will send.
- * Clean-up DHT transaction code, it's just nasty.
  * Handle wanted pieces more efficiently, it's slow in in fillRequests, since the prioritization system was changed.
- * Determine if we should accept connections, even if we just close them. http://stackoverflow.com/questions/35108571/can-i-leave-sockets-in-syn-recv-until-im-interested-in-accepting
- * Implement BEP 40.
- * Move tracker management code in the torrent package to its own file.