title: Yii2 migration problems
body: <p>I am using yii2 for the first time, and I wanna trying yii migrations.
  The problem:
  I created migration file with</p>
  
  <p><code>php yii migrate/create new_table</code></p>
  
  <p>file is created. then I input new table details into migration file.
  and when I run <code>php yii migrate</code>
  I got error </p>
  
  <p><code>Exception 'ReflectionException' with message 'Class db does not exist'<br>
  in /var/www/yii2.uz/vendor/yiisoft/yii2/di/Container.php:415
  </code>
  what's the problem?</p>
  
  <p>my <code>console/config/main.php</code>: </p>
  
  <pre><code>&lt;?php 
  $params = array_merge(
      require(__DIR__ . '/../../common/config/params.php'),
      require(__DIR__ . '/../../common/config/params-local.php'),
      require(__DIR__ . '/../../common/config/main-local.php'),
      require(__DIR__ . '/params.php'),
      require(__DIR__ . '/params-local.php')
      ); 
      return [
      'id' =&gt; 'app-console',
      'basePath' =&gt; dirname(__DIR__),
      'bootstrap' =&gt; ['log'],
      'controllerNamespace' =&gt; 'console\controllers',
      'components' =&gt; [
          'log' =&gt; [
              'targets' =&gt; [
                  [
                      'class' =&gt; 'yii\log\FileTarget',
                      'levels' =&gt; ['error', 'warning'],
                  ],
              ],
          ],
      ],
      'params' =&gt; $params,
      ];
  </code></pre>
  
  <p>and my migration file:</p>
  
  <pre><code>&lt;?php use yii\db\Schema;
        use yii\db\Migration;
  
        class m150727_125205_new_table extends Migration
        {
         public function up()
        {
          $this-&gt;createTable('test',[
             'id'=&gt; Schema::TYPE_PK,
              'name'=&gt;  Schema::TYPE_STRING
          ]);
      }
  
      public function down()
      {
          echo "m150727_125205_new_table cannot be reverted.\n";
  
          return false;
      }
  </code></pre>