Инициализировано Yii2 приложение, выпилены лишние части, накинуты чуточку нужных

environments/dev/common/config/main-local.php

@@ -0,0 +1,16 @@
+<?php
+return [
+    'components' => [
+        'db' => [
+            'dsn' => 'mysql:host=localhost;dbname=ely_accounts',
+            'username' => 'root',
+            'password' => '',
+        ],
+        'mailer' => [
+            // send all mails to a file by default. You have to set
+            // 'useFileTransport' to false and configure a transport
+            // for the mailer to send real emails.
+            'useFileTransport' => true,
+        ],
+    ],
+];

environments/dev/common/config/params-local.php

@@ -0,0 +1,3 @@
+<?php
+return [
+];