Aligned setting helper with new get method changes

Also removed old unsused facade that existed for settings.

app/Config/app.php

@@ -183,7 +183,6 @@ return [
 
         // Custom BookStack
         'Activity' => BookStack\Facades\Activity::class,
-        'Setting'  => BookStack\Facades\Setting::class,
         'Views'    => BookStack\Facades\Views::class,
         'Images'   => BookStack\Facades\Images::class,
         'Permissions' => BookStack\Facades\Permissions::class,

app/Facades/Setting.php

@@ -1,16 +0,0 @@
-<?php namespace BookStack\Facades;
-
-use Illuminate\Support\Facades\Facade;
-
-class Setting extends Facade
-{
-    /**
-     * Get the registered name of the component.
-     *
-     * @return string
-     */
-    protected static function getFacadeAccessor()
-    {
-        return 'setting';
-    }
-}

app/Providers/CustomFacadeProvider.php

@@ -5,7 +5,6 @@ namespace BookStack\Providers;
 use BookStack\Actions\ActivityService;
 use BookStack\Actions\ViewService;
 use BookStack\Auth\Permissions\PermissionService;
-use BookStack\Settings\SettingService;
 use BookStack\Uploads\ImageService;
 use Illuminate\Support\ServiceProvider;
 
@@ -36,10 +35,6 @@ class CustomFacadeProvider extends ServiceProvider
             return $this->app->make(ViewService::class);
         });
 
-        $this->app->singleton('setting', function () {
-            return $this->app->make(SettingService::class);
-        });
-
         $this->app->singleton('images', function () {
             return $this->app->make(ImageService::class);
         });

app/helpers.php

@@ -79,9 +79,9 @@ function userCanOnAny(string $permission, string $entityClass = null): bool
 
 /**
  * Helper to access system settings.
- * @return bool|string|SettingService
+ * @return mixed|SettingService
  */
-function setting(string $key = null, $default = false)
+function setting(string $key = null, $default = null)
 {
     $settingService = resolve(SettingService::class);