Upgrade to latest Rust
Upgrade to latest Rust

bjz/glfw-rs,nstoddard/glfw-rs,derekdreery/glfw-rs,derekdreery/glfw-rs,mneumann/glfw-rs,servo/glfw-rs,bvssvni/glfw-rs,PistonDevelopers/glfw-rs,tomaka/glfw-rs