chg: [users:index] Added setting to allow the deletion of users

Fix #119

src/Controller/UsersController.php

@@ -308,6 +308,9 @@ class UsersController extends AppController
         }
         $params = [
             'beforeSave' => function($data) use ($currentUser, $validRoles) {
+                if (empty(Configure::read('user.allow-user-deletion'))) {
+                    throw new MethodNotAllowedException(__('User deletion is disabled on this instance.'));
+                }
                 if (!$currentUser['role']['perm_admin']) {
                     if ($data['organisation_id'] !== $currentUser['organisation_id']) {
                         throw new MethodNotAllowedException(__('You do not have permission to delete the given user.'));

src/Model/Table/SettingProviders/CerebrateSettingsProvider.php

@@ -342,7 +342,13 @@ class CerebrateSettingsProvider extends BaseSettingsProvider
                             'type' => 'boolean',
                             'description' => __('This setting will enforce that usernames conform to basic requirements of e-mail addresses.'),
                             'default' => false
-                        ]
+                        ],
+                        'user.allow-user-deletion' => [
+                            'name' => __('Allow user deletion'),
+                            'type' => 'boolean',
+                            'description' => __('This setting will allow the deletion of users by authorized users.'),
+                            'default' => false
+                        ],
                     ]
                 ]
             ]

templates/Users/index.php

@@ -145,6 +145,9 @@ echo $this->element('genericElements/IndexTable/index_table', [
                         ]
                     ],
                     'function' => function ($row, $options)  use ($loggedUser, $validRoles) {
+                        if (empty(Configure::read('user.allow-user-deletion'))) {
+                            return false;
+                        }
                         if ($row['id'] == $loggedUser['id']) {
                             return false;
                         }