Add Apache and MIT license texts?

[edunham]

Probably same as https://github.com/rust-lang/regex . They're referred to by the COPYRIGHT file but not provided in this repo

re: rust-lang/rust#25664

[brson]

Yes. Furthermore, the COPYRIGHT file in this repo looks totally bogus to me. It's an ancient clone of the Rust COPYRIGHT file, probably added with the intent of placing the Rust license somewhere stable, not as the license for this repo. Still - I think we should assume this repo is MIT/ASL2 and fix the license.