Add PHP History timeline

[pronskiy]

Hey folks,

Back in 2020, we at JetBrains put together this timeline of PHP’s history: https://jb.gg/php25.
The event data is open source: https://github.com/JetBrains/php-timeline. But since the site isn’t dynamic, it hasn’t really been updated since.

I was thinking it might make sense to move it over to php.net, maybe under something like https://www.php.net/history.

@mkurzeja kindly offered to help with the implementation.

@saundefined @samdark @sebastianbergmann — what do you think?

[saundefined]

Sounds great to me

[samdark]

Awesome idea.