title: Avoid repeating base_url in the config.php
body: <p>I am writing custom configs in my <code>config.php</code> file in codeigniter but from development to production,there is lots of work renaming my custom configs to reflect the new domain.</p>
  
  <p>For instance</p>
  
  <pre><code>$config['base_url'] = 'http://localhost/_init/';
  
  $config['media_player_js']  = 'http://localhost/assets/';
  
  $config['media_player_css'] = 'http://localhost/_init/';
  
  $config['videos']   = 'http://localhost/_init/';
  
  $config['audios']   = 'http://localhost/_init/';
  </code></pre>
  
  <p>I have had to repeat the base url four times.Is <code>$config['base_url']</code> variable available for use inside of the <code>config.php</code> file?.</p>