TODO pack decoding + pack exploding

• parallel
  • limit parallelism by allowing to set the amount of threads
• pack
  • extract borrowed objects from a pack
  • support streamed objects (similar to how it's done with loose objects) - no need, all slices support io::Read, and we don't actually support streaming, so let's net unify 'interfaces' on a low level like this.
• owned objects
  • encode object
    • blob
    • tag
    • tree
    • commit
• pack verify
  • add '--some-flag' to run every non-blob through a decode/encode cycle to see if all objects can be parsed
  • The Linux Kernel verifies --decode and --re-encode
    • parse pgp_signature and mergetag into 'extra-headers' without further parsing
  • The Rust repo verifies --decode and --re-encode
  • add re-encode to all stress tests
  • support easy access to merge-tags and the signature
• stream pack for verify-pack
  • support for multi-threading
  • choice of algorithm in pack-verify
  • use pack streaming in pack-verify by default
  • set some unit tests cases to use the streaming algorithm
• progress - convenience
  • inc() method andinc_by(step) method
• plumbing - explode pack
  • useful for receiving packs that are small enough to warrant living as loose objects for a while preventing pack buildup
  • write loose object
  • multi-threaded
  • progress
  • statistics
• index-from-pack
  • capability to receive packs from a stream
• multi-db (incorporate object lookup for loose objects and packs)
  • single threaded
  • optional object cache
  • fs-check - verify all object content of a git repository
• progress - convenience
  • a way to measure throughput on drop
  • percentages somewhere near the progress bar