title: Codeigniter in subdomain issue
body: <p>I have a CodeIgniter instance in a web server subdirectory, <strong>www/CI</strong>.
  My <strong>www/CI/application/config/config.php</strong> file is configured with:</p>
  
  <pre><code>$config['base_url'] = 'http://CI.example.com/';
  </code></pre>
  
  <p>I also have a subdomain '<strong>CI.example.com</strong>' pointing to that CI directory. My <strong>www/CI/.htaccess</strong> file is just the standard in these cases for removing the 'index.php' string:</p>
  
  <pre><code>RewriteEngine on 
  RewriteBase /
  RewriteCond $1 !^(index\.php|assets|robots\.txt|favicon\.ico)
  RewriteCond %{REQUEST_FILENAME} !-f
  RewriteCond %{REQUEST_FILENAME} !-d
  RewriteRule ^(.*)$ index.php?/$1 [L]
  </code></pre>
  
  <p>Every URL inside my CI app is working fine, except the root one: 'CI.example.com'. When I try to access this one, the directives in <strong>www/.htaccess</strong> (the upper, main domain) are applied and this results in an undesired behaviour...</p>
  
  <p>Could you help with this issue?
  Thanks in advance.</p>