Issue #558: Implement bin/generate-openapi.php to generate OpenAPI documentation

Signed-off-by: alexmerlin <alex.merlin.1985@gmail.com>

Author: alexmerlin

config/autoload/local.php.dist

@@ -77,4 +77,7 @@ return [
         ],
     ],
     'userAnonymizeAppend' => '',
+    'openapi'             => [
+        'server_description' => 'Development server',
+    ],
 ];

config/autoload/openapi.global.php

@@ -94,7 +94,6 @@
             'UserAvatar'      => 'User and account avatars.',
             'UserRole'        => 'User role catalogue.',
         ],
-        'server_description' => 'Local development server',
         'security_schemes'   => [
             'AuthToken'           => [
                 'type'          => 'http',