Sessions - deprecated getter for expireDelta

[Lumeriol]

Version: 4.0-dev

Bug Description

There is similar problem with deprecated reading from Session section as https://github.com/nette/application/issues/314

Steps To Reproduce

Set cookie with expiration (i. e. login form)

Possible Solution

Change this line of code:

https://github.com/nette/security/blob/d465cb69ea630d67d027f912d133d2aec04cb98a/src/Bridges/SecurityHttp/SessionStorage.php#L148

to

 $section->set('expireTime', time() + $section->get('expireDelta')); // sliding expiration