message: Drop nightly feature
  Forgot to remove after being done with valgrind
diff: //! Alacritty - The GPU Enhanced Terminal
  #![cfg_attr(feature = "clippy", plugin(clippy))]
  #![cfg_attr(feature = "clippy", feature(plugin))]
  -#![feature(alloc_system)] extern crate alloc_system;
  #[macro_use]
  extern crate alacritty;
  