Add features list to README

[UntaggedLady]

I wish the readme indicated what features this tool supports, compared to other tools like magnetico.

• Does this tool show seed/peer numbers?
• Does this tool allow sorting by seed/peer numbers?
• Does this tool have download rate limiting? Max file size limitting?
• Is this tool ready to be deployed public-facing, or is it intended for local/private deployment only?

For a list of other features that you may want to add to the README, see magnetico's feature list.