Replace isatty crate with atty

The `isatty` crate has been deprecated and a replacement has been
released for it called `atty`. It offers a nicer API and the code
change to adapt is trivial.

Signed-off-by: Otavio Salvador <[email protected]>

Author: otavio

Cargo.lock

@@ -32,7 +32,7 @@ cargo-fmt = []
 rustfmt-format-diff = []
 
 [dependencies]
-isatty = "0.1"
+atty = "0.2"
 itertools = "0.7"
 toml = "0.4"
 serde = "1.0"

Cargo.toml

@@ -12,7 +12,7 @@ use config::config_type::ConfigType;
 use config::lists::*;
 use config::{Config, FileName};
 
-use isatty::stdout_isatty;
+use atty;
 
 use std::collections::HashSet;
 use std::path::{Path, PathBuf};
@@ -297,7 +297,7 @@ impl Color {
         match self {
             Color::Always => true,
             Color::Never => false,
-            Color::Auto => stdout_isatty(),
+            Color::Auto => atty::is(atty::Stream::Stdout),
         }
     }
 }

src/config/options.rs

@@ -16,9 +16,9 @@
 
 #[macro_use]
 extern crate derive_new;
+extern crate atty;
 extern crate diff;
 extern crate failure;
-extern crate isatty;
 extern crate itertools;
 #[cfg(test)]
 #[macro_use]