Type and simplify is_known_*() helpers

Update status_header() helper function

Modernize a term lookup map slightly

Fix 8.0.8 signatures

The old signatures were from 8.0.8RC1.

Announce 7.4.21

8.0.8 is security

Announce PHP 8.0.8

Announce 7.3.29

7.4.21 tarballs

7.3.29 tarballs

Announce 8.1.0alpha2

Update 2021-06-21-1.xml

Closes GH-412.

Announcing International PHP Conference Munich 2021

Closes GH-411.

Fixed typo

Announce 8.1.0alpha1

Remove reference to Freenode and replace with Libera.Chat (#409)

Co-authored-by: Jez Emery <jez@bmssalvage.co.uk>

Add minor links to sidebar and unify rendering (changelog)

Add missing close section tag

Add sidebar to ChangeLog rendering for navigating between versions

Announce 8.0.7

Announce 7.4.20

8.0.7 tarballs

7.4.20 tarballs

Fix #81089: Dead link in php.ini: http://php.net/session.sid-length

Longhorn PHP 2021 CFP

Closes-GH 410.