Always show warning if an app requires email to be enabled for the selected domain

We can be smarter in the future and show this based on currently
selected domain from the dropdown

webadmin/src/views/apps.js

@@ -10,7 +10,6 @@ angular.module('Application').controller('AppsController', ['$scope', '$location
     $scope.domains = [];
     $scope.groups = [];
     $scope.users = [];
-    $scope.mailConfig = {};
     $scope.backupConfig = {};
 
     $scope.appConfigure = {
@@ -497,14 +496,6 @@ angular.module('Application').controller('AppsController', ['$scope', '$location
         });
     }
 
-    function getMailConfig() {
-        Client.getMailConfig(function (error, mailConfig) {
-            if (error) return console.error(error);
-
-            $scope.mailConfig = mailConfig;
-        });
-    }
-
     function getBackupConfig() {
         Client.getBackupConfig(function (error, backupConfig) {
             if (error) return console.error(error);
@@ -521,7 +512,6 @@ angular.module('Application').controller('AppsController', ['$scope', '$location
                 fetchUsers();
                 fetchGroups();
                 getDomains();
-                getMailConfig();
                 getBackupConfig();
             }