DP-342 Test datasource connection upon service creation

- add app_debug to environment endpoint

Author: yaroslavmo

src/Resources/Environment.php

@@ -83,6 +83,7 @@ protected function handleGET()
                 $result['platform']['install_path'] = base_path() . DIRECTORY_SEPARATOR;
                 $result['platform']['log_path'] = env('DF_MANAGED_LOG_PATH',
                         storage_path('logs')) . DIRECTORY_SEPARATOR;
+                $result['platform']['app_debug'] = env('APP_DEBUG', false);
                 $result['platform']['log_mode'] = \Config::get('logging.log');
                 $result['platform']['log_level'] = \Config::get('logging.log_level');
                 $result['platform']['cache_driver'] = \Config::get('cache.default');