Use the Operable styleguide repository for Ebert

Also remove direct Credo dependency, and add an Ebert badge to the README.

.ebert.yml

@@ -0,0 +1,11 @@
+styleguide: operable/linters
+engines:
+  credo:
+    enabled: true
+  fixme:
+    enabled: true
+  remark-lint:
+    enabled: true
+exclude_paths:
+- config
+- test

README.md

@@ -1,6 +1,7 @@
 # Cog
 
 [![Build Status](https://travis-ci.org/operable/cog.svg?branch=master)](https://travis-ci.org/operable/cog)
+[![Ebert](https://ebertapp.io/github/operable/cog.svg)](https://ebertapp.io/github/operable/cog)
 
 Cog brings the power of the command line to the place you collaborate with your team all the time -- your chat window.
 

mix.exs

@@ -114,7 +114,6 @@ defmodule Cog.Mixfile do
 
       # Test and Development
       ########################################################################
-      {:credo, "~> 0.4", only: [:dev, :test]},
       {:earmark, "~> 1.0", only: :dev},
       {:ex_doc, "~> 0.13", only: :dev},
       {:excoveralls, "~> 0.5", only: :test},

mix.lock

@@ -1,13 +1,11 @@
 %{"bamboo": {:hex, :bamboo, "0.7.0", "2722e395a396dfedc12d300c900f65b216f7d7bf9d430c5dd0235690997878b7", [:mix], [{:httpoison, "~> 0.9", [hex: :httpoison, optional: false]}, {:plug, "~> 1.0", [hex: :plug, optional: false]}, {:poison, ">= 1.5.0", [hex: :poison, optional: false]}]},
   "bamboo_smtp": {:hex, :bamboo_smtp, "1.2.1", "47181e338cbee9d028e94f2bc5829816b26d719d8213b07d0fa107d95b591947", [:mix], [{:bamboo, "~> 0.7.0", [hex: :bamboo, optional: false]}, {:gen_smtp, "~> 0.11.0", [hex: :gen_smtp, optional: false]}]},
-  "bunt": {:hex, :bunt, "0.1.6", "5d95a6882f73f3b9969fdfd1953798046664e6f77ec4e486e6fafc7caad97c6f", [:mix], []},
   "certifi": {:hex, :certifi, "0.4.0", "a7966efb868b179023618d29a407548f70c52466bf1849b9e8ebd0e34b7ea11f", [:rebar3], []},
   "comeonin": {:hex, :comeonin, "2.5.3", "ccd70ebf465eaf4e11fc5a13fd0f5be2538b6b4975d4f7a13d571670b31da060", [:make, :mix], []},
   "conduit": {:git, "https://github.com/operable/conduit.git", "4b1ac0547dc11cb474ba9e274bf277038205e0b5", []},
   "connection": {:hex, :connection, "1.0.4", "a1cae72211f0eef17705aaededacac3eb30e6625b04a6117c1b2db6ace7d5976", [:mix], []},
   "cowboy": {:hex, :cowboy, "1.0.4", "a324a8df9f2316c833a470d918aaf73ae894278b8aa6226ce7a9bf699388f878", [:make, :rebar], [{:cowlib, "~> 1.0.0", [hex: :cowlib, optional: false]}, {:ranch, "~> 1.0", [hex: :ranch, optional: false]}]},
   "cowlib": {:hex, :cowlib, "1.0.2", "9d769a1d062c9c3ac753096f868ca121e2730b9a377de23dec0f7e08b1df84ee", [:make], []},
-  "credo": {:hex, :credo, "0.4.12", "f5e1973405ea25c6e64959fb0b6bf92950147a0278cc2a002a491b45f78f7b87", [:mix], [{:bunt, "~> 0.1.6", [hex: :bunt, optional: false]}]},
   "db_connection": {:hex, :db_connection, "1.0.0", "63c03e520d54886a66104d34e32397ba960db6e74b596ce221592c07d6a40d8d", [:mix], [{:connection, "~> 1.0.2", [hex: :connection, optional: false]}, {:poolboy, "~> 1.5", [hex: :poolboy, optional: true]}, {:sbroker, "~> 1.0", [hex: :sbroker, optional: true]}]},
   "decimal": {:hex, :decimal, "1.2.0", "462960fd71af282e570f7b477f6be56bf8968e68277d4d0b641a635269bf4b0d", [:mix], []},
   "earmark": {:hex, :earmark, "1.0.2", "a0b0904d74ecc14da8bd2e6e0248e1a409a2bc91aade75fcf428125603de3853", [:mix], []},