Merge pull request #24 from kkawakam/UpgradeLibraries

Updating libc and nix dependencies
diff --git a/Cargo.toml b/Cargo.toml
index 7e1d8e2..b568d4c 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -10,8 +10,8 @@
 license = "MIT"
 
 [dependencies]
-libc = "0.2.1"
-nix = "0.4.1"
+libc = "0.2.7"
+nix = "0.5.0"
 unicode-width = "0.1.3"
 
 [dev-dependencies]