Plugin.php

<?php

namespace Martin\GitReposManager;

use Backend, Controller, Lang, Validator;
use System\Classes\PluginBase;
use System\Classes\SettingsManager;

class Plugin extends PluginBase {

    public function pluginDetails() {
        return [
            'name'        => 'martin.gitreposmanager::lang.plugin.name',
            'description' => 'martin.gitreposmanager::lang.plugin.description',
            'author'      => 'Martin M.',
            'homepage'    => 'https://github.com/skydiver/',
            'icon'        => 'icon-cubes'
        ];
    }

    public function boot() {

        Validator::extend('isReadable', function ($attribute, $value, $parameters, $validator) {
            if (is_readable($value)) {
                return true;
            } else {
                return false;
            }
        }, Lang::get('martin.gitreposmanager::lang.model.errors.validator_is_readable'));

    }

    public function registerSettings() {
        return [
            'gitreposmanager' => [
                'label'       => 'martin.gitreposmanager::lang.navigation.label',
                'description' => 'martin.gitreposmanager::lang.navigation.description',
                'category'    => SettingsManager::CATEGORY_SYSTEM,
                'icon'        => 'icon-git',
                'url'         => Backend::url('martin/gitreposmanager/repos'),
                'order'       => 500,
                'permissions' => ['martin.gitreposmanager.access_repos'],
            ]
        ];
    }

    public function registerPermissions() {
        return [
            'martin.gitreposmanager.access_repos' => ['label' => 'Access Git Repos Manager page', 'tab' => 'Git Repos Manager'],
        ];
    }

}

?>