feat(articles): Article Admin feature (#807)

This feature introduces a breaking change, that restricts the User's that
can create/edit/delete Articles to only those that have the `admin` Role.

Fixed ESLint issues.

Resolved merge conflicts, and moved new client Article Service
`createOrUpdate` functionality to new Admin feature controller.

Removed edit functionality from client-side Article controller.

modules/articles/client/controllers/admin/article.client.controller.js

@@ -0,0 +1,48 @@
+(function () {
+  'use strict';
+
+  angular
+    .module('articles.admin')
+    .controller('ArticlesController', ArticlesController);
+
+  ArticlesController.$inject = ['$scope', '$state', '$window', 'articleResolve', 'Authentication'];
+
+  function ArticlesController($scope, $state, $window, article, Authentication) {
+    var vm = this;
+
+    vm.article = article;
+    vm.authentication = Authentication;
+    vm.error = null;
+    vm.form = {};
+    vm.remove = remove;
+    vm.save = save;
+
+    // Remove existing Article
+    function remove() {
+      if ($window.confirm('Are you sure you want to delete?')) {
+        vm.article.$remove($state.go('admin.articles.list'));
+      }
+    }
+
+    // Save Article
+    function save(isValid) {
+      if (!isValid) {
+        $scope.$broadcast('show-errors-check-validity', 'vm.form.articleForm');
+        return false;
+      }
+
+      // Create a new article, or update the current instance
+      vm.article.createOrUpdate()
+        .then(successCallback)
+        .catch(errorCallback);
+
+      function successCallback(res) {
+        $state.go('admin.articles.list'); // should we send the User to the list or the updated Article's view?
+      }
+
+      function errorCallback(res) {
+        vm.error = res.data.message;
+      }
+    }
+  }
+}());