Fatal error on call function get_magic_quotes_gpc()

[dimayakovlev]

Function `get_magic_quotes_gpc() has been DEPRECATED as of PHP 7.4.0, and REMOVED as of PHP 8.0.0.

Remove all code where get_magic_quotes_gpc() used or check PHP version before execute function.

To compare PHP version use code:

<?php
if (version_compare(PHP_VERSION, '7.4.0', '<')) {
  // use get_magic_quotes_gpc()
}

Part of #83.

[dimayakovlev]

Prefer to compare PHP version to preserve compatibility.