[ticket/12610] Add return status and doc blocks

Add a return status for command update:check.

PHPBB3-12610
[ticket/12610] Modify messages

PHPBB3-12610
[ticket/12610] Modify messages

PHPBB3-12610
Merge branch 'ticket/12610' of github.com:ptitlazy/phpbb into ticket/12610

Conflicts:
	phpBB/phpbb/console/command/update/check.php
Merge pull request #4 from ptitlazy/ticket/12610

[ticket/12610] Add return status and doc blocks