Varien_Io_File analog in Magento 2

Development
1

The functionality of Magento 1.x Varien_Io_File has been moved to \Magento\Framework\Filesystem\Io\File class in Magento 2.

So, for example, to delete folder recursive use

\Magento\Framework\Filesystem\Io\File::rmdirRecursive($path);

insead of

Varien_Io_File::rmdirRecursive($path);