colorized stdout logger if stdout is tty

Gopkg.lock

@@ -17,6 +17,14 @@
   revision = "346938d642f2ec3594ed81d874461961cd0faa76"
   version = "v1.1.0"
 
+[[projects]]
+  digest = "1:e988ed0ca0d81f4d28772760c02ee95084961311291bdfefc1b04617c178b722"
+  name = "github.com/fatih/color"
+  packages = ["."]
+  pruneopts = ""
+  revision = "5b77d2a35fb0ede96d138fc9a99f5c9b6aef11b4"
+  version = "v1.7.0"
+
 [[projects]]
   branch = "master"
   digest = "1:5d0a2385edf4ba44f3b7b76bc0436ceb8f62bf55aa5d540a9eb9ec6c58d86809"
@@ -81,6 +89,14 @@
   pruneopts = ""
   revision = "7cafcd837844e784b526369c9bce262804aebc60"
 
+[[projects]]
+  digest = "1:9ea83adf8e96d6304f394d40436f2eb44c1dc3250d223b74088cc253a6cd0a1c"
+  name = "github.com/mattn/go-colorable"
+  packages = ["."]
+  pruneopts = ""
+  revision = "167de6bfdfba052fa6b2d3664c8f5272e23c9072"
+  version = "v0.0.9"
+
 [[projects]]
   digest = "1:78229b46ddb7434f881390029bd1af7661294af31f6802e0e1bedaad4ab0af3c"
   name = "github.com/mattn/go-isatty"
@@ -255,6 +271,7 @@
   analyzer-name = "dep"
   analyzer-version = 1
   input-imports = [
+    "github.com/fatih/color",
     "github.com/go-logfmt/logfmt",
     "github.com/go-yaml/yaml",
     "github.com/golang/protobuf/proto",