The fact that copyrighted works were included in the readme shows it was intended for that use, and the RIAA complaint will likely stand up to any legal scrutiny. Just because it can be used for legit purposes too won't matter in the slightest. I mean, Napster could have been used for legal means as well, and it got destroyed in court.
The only chance tools like this have legally is when infringement is an "unintended side effect."
The only chance tools like this have legally is when infringement is an "unintended side effect."