Invalid callback elFinderSession::session_start_error

[gonandriy]

Using with Symfony 3.4 I get PHP Warning

PHP Warning: Invalid callback elFinderSession::session_start_error, cannot access protected method elFinderSession::session_start_error() in ../vendor/symfony/symfony/src/Symfony/Component/HttpFoundation/Session/Storage/Handler/StrictSessionHandler.php on line 101

Might it be worth to make the method public?

[nao-pon]

@gonandriy When integrating with other frameworks that use sessions, it may be convenient to use your own session handler.

• https://github.com/Studio-42/elFinder/wiki/Connector-configuration-options-2.1#session-218