Sessions are not cleaned up

[fbartels]

My backups of 2fauth were taking quite long so I checked the size of the backup. The app stores some session data in /app/data/storage/framework/sessions, which does not seem to get cleaned up.

/app/data/storage/framework/sessions# find . -type f -printf x | wc -c
719188

With that amount of files it was not possible to list files with ls, which resulted Killed being printed on the console.

[girish]

Looks like upstream has this hardcoded to 90 days - https://github.com/Bubka/2FAuth/blob/master/config/session.php#L34

[girish]

I have moved the session files out of the data directory now. Maybe we should move to redis even later.