rustup to rustc 1.16.0-nightly (7821a9b99 2017-01-23)
rustup to rustc 1.16.0-nightly (7821a9b99 2017-01-23)

See
https://github.com/rust-lang/rust/commit/03620dba25328ee8cc7316cf6d9bad2d0a118ba1
for changes in libsyntax.

zsiciarz/docopt.rs,zsiciarz/docopt.rs,zsiciarz/docopt.rs