Update ember-cli and friends

- Use yarn
- Remove bower
- Remove files unnecessary for a node addon
- Switch from jshint to eslint
- Clean up tests

Author: lukemelia

.bowerrc

@@ -0,0 +1,13 @@
+module.exports = {
+  root: true,
+  parserOptions: {
+    ecmaVersion: 6,
+    sourceType: 'module'
+  },
+  extends: 'eslint:recommended',
+  env: {
+    browser: true
+  },
+  rules: {
+  }
+};

.eslintrc.js

@@ -1,23 +1,19 @@
 ---
 language: node_js
 node_js:
-  - "0.12"
+  - "6"
 
 sudo: false
 
 cache:
-  directories:
-    - node_modules
-
-matrix:
-  fast_finish: true
+  yarn: true
 
 before_install:
-  - "npm config set spin false"
-  - "npm install -g npm@^2"
+  - curl -o- -L https://yarnpkg.com/install.sh | bash
+  - export PATH=$HOME/.yarn/bin:$PATH
 
 install:
-  - npm install
+  - yarn install --no-lockfile
 
 script:
-  - npm test
+  - yarn test

.jshintrc

@@ -138,6 +138,10 @@ to see how you can customize your messages.
 
 ## Running Tests
 
-- `npm test`
+* `yarn test`
+
+## Why `ember build` and `ember test` don't work
+
+Since this is a node-only ember-cli addon, this package does not include many files and dependencies which are part of ember-cli's typical `ember build` and `ember test` processes.
 
 [2]: http://ember-cli-deploy.com/docs/v0.6.x/plugins-overview/ "Plugin Documentation"

.travis.yml

@@ -1,7 +1,6 @@
-/* jshint node: true */
+/*eslint-env node*/
 'use strict';
 
-var SilentError   = require('silent-error');
 var SlackNotifier = require('./lib/slack-notifier');
 var DeployPluginBase = require('ember-cli-deploy-plugin');
 
@@ -16,15 +15,15 @@ module.exports = {
       defaultConfig: {
         enabled: true,
 
-        willDeploy: function(context) {
-          return function(slack){
+        willDeploy: function(/* context */) {
+          return function(/* slack */){
             return {
               slackStartDeployDate: new Date()
             };
           }
         },
 
-        didDeploy: function(context) {
+        didDeploy: function(/* context */) {
           return function(slack){
             var startDeployDate    = this.context.slackStartDeployDate;
             var endDeployDate      = new Date();
@@ -48,7 +47,7 @@ module.exports = {
           };
         },
 
-        didFail: function(context) {
+        didFail: function(/* context */) {
           return function(slack) {
             var message = "Ember-cli-deploy tried to deploy a revision but failed.";