SessionStorage::setupExpiration() nette/http v3.4.0 compatibility

[forgie1]

Closes #76

[becygroup]

It is not enough. Even the expiration is provided, needs to be converted to relative from absolute timestamp.

nette/security/src/Bridges/SecurityHttp/SessionStorage.php:73:

$this->expireTime = $time ? (int) Nette\Utils\DateTime::from($time)->format('U') : null;

Needs to be converted to relative time when section expiration is set in

nette/security/src/Bridges/SecurityHttp/SessionStorage.php:94

$section->setExpiration((string) ($this->expireTime - time()), 'foo'); // time check

or something similar.