Use credo in strict mode

.travis.yml

@@ -7,6 +7,7 @@ otp_release:
 script:
   - MIX_ENV=test mix deps.get
   - MIX_ENV=test mix test
+  - MIX_ENV=test mix credo --strict
 after_script:
   - MIX_ENV=test mix coveralls.travis
   - MIX_ENV=docs mix deps.get

mix.exs

@@ -57,7 +57,8 @@ defmodule ExrmDeb.Mixfile do
      {:timex, "~> 3.0"},
      {:vex, "~> 0.5"},
      {:swab, github: "crownedgrouse/swab", branch: "master"},
-     {:dogma, "~> 0.1", only: :dev}
+     {:dogma, "~> 0.1", only: [:dev, :test]},
+     {:credo, "~> 0.4", only: [:dev, :test]}
     ]
   end
 

mix.lock

@@ -1,7 +1,9 @@
 %{"bbmustache": {:hex, :bbmustache, "1.0.4", "7ba94f971c5afd7b6617918a4bb74705e36cab36eb84b19b6a1b7ee06427aa38", [:rebar], []},
+  "bunt": {:hex, :bunt, "0.1.6", "5d95a6882f73f3b9969fdfd1953798046664e6f77ec4e486e6fafc7caad97c6f", [:mix], []},
   "certifi": {:hex, :certifi, "0.4.0", "a7966efb868b179023618d29a407548f70c52466bf1849b9e8ebd0e34b7ea11f", [:rebar3], []},
   "cf": {:hex, :cf, "0.2.1", "69d0b1349fd4d7d4dc55b7f407d29d7a840bf9a1ef5af529f1ebe0ce153fc2ab", [:rebar3], []},
   "combine": {:hex, :combine, "0.9.2", "cd3c8721f378ebe032487d8a4fa2ced3181a456a3c21b16464da8c46904bb552", [:mix], []},
+  "credo": {:hex, :credo, "0.4.12", "f5e1973405ea25c6e64959fb0b6bf92950147a0278cc2a002a491b45f78f7b87", [:mix], [{:bunt, "~> 0.1.6", [hex: :bunt, optional: false]}]},
   "dogma": {:hex, :dogma, "0.1.8", "1ee856ed64f3ad635a4b2127beea427ea1b9bc271b8731679a97938e1827730f", [:mix], [{:poison, ">= 1.0.0", [hex: :poison, optional: false]}]},
   "earmark": {:hex, :earmark, "0.2.1", "ba6d26ceb16106d069b289df66751734802777a3cbb6787026dd800ffeb850f3", [:mix], []},
   "erlware_commons": {:hex, :erlware_commons, "0.21.0", "a04433071ad7d112edefc75ac77719dd3e6753e697ac09428fc83d7564b80b15", [:rebar3], [{:cf, "0.2.1", [hex: :cf, optional: false]}]},