[ticket/13232] Use a cache var with _ to force TTL and shuffle cron tasks

PHPBB3-13232
[ticket/13232] Fix indentation

PHPBB3-13232
[ticket/13232] Fix more issues with TTL and global cache file

PHPBB3-13232
[ticket/13234-2] Never allow autologin/remember me to modify the userid

Ascraeus version of 64d97d0787a63b3c646f89237574ac566ed89c50 commit

PHPBB3-13234
[ticket/13234-2] Correctly verify that user_id is set in user data array

PHPBB3-13234-2
Merge branch 'naderman-ticket/13232' into prep-release-3.1.0
Merge branch 'prep-release-3.1.0' into develop-ascraeus
Merge branch 'develop-ascraeus' into develop
Merge pull request #3091 from Nicofuma/ticket/13234-2

Ticket/13234 2
Merge branch 'prep-release-3.1.0' into develop-ascraeus
Merge branch 'develop-ascraeus' into develop
[prep-release-3.1.0] Update changelog with final changes
Merge branch 'prep-release-3.1.0' into develop-ascraeus
Merge branch 'develop-ascraeus' into develop