Merge pull request #37 from softprops/support-older-versions-of-rust

Support older versions of rust
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 0477759..8a8983b 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,7 @@
+# 0.2.13
+
+* support older versions of rust that do now support 2018 edition
+
 # 0.2.12
 
 * Redox is now in the unix family so redox cfg is no longer needed [#35](https://github.com/softprops/atty/pull/35)
diff --git a/Cargo.toml b/Cargo.toml
index 61982ab..7351a2f 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "atty"
-version = "0.2.12"
+version = "0.2.13"
 authors = ["softprops <d.tangren@gmail.com>"]
 description = "A simple interface for querying atty"
 documentation = "http://softprops.github.io/atty"
@@ -10,7 +10,6 @@
 license = "MIT"
 readme = "README.md"
 exclude = ["/.travis.yml", "/appveyor.yml"]
-edition = "2018"
 
 [badges]
 travis-ci = { repository = "softprops/atty" }
diff --git a/examples/atty.rs b/examples/atty.rs
index 19cbcda..3b3635e 100644
--- a/examples/atty.rs
+++ b/examples/atty.rs
@@ -1,3 +1,5 @@
+extern crate atty;
+
 use atty::{is, Stream};
 
 fn main() {
diff --git a/src/lib.rs b/src/lib.rs
index af9538d..89b7555 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -17,6 +17,11 @@
 
 #![cfg_attr(unix, no_std)]
 
+#[cfg(unix)]
+extern crate libc;
+#[cfg(windows)]
+extern crate winapi;
+
 #[cfg(windows)]
 use winapi::shared::minwindef::DWORD;
 #[cfg(windows)]