Enable specifying explicit list of external posts to display

[alshedivat]

• updates external-posts.rb plugin, allowing the user to specify an explicit lists of urls in _config.yml that are then displayed in the blog feed as external posts
• 99% of the code in this change is written by gpt-4: https://chat.openai.com/share/24432d24-36a7-4d6f-a5c0-d7e5142f68cd

[george-gca]

How does it work? Maybe it would be a good idea to add an example of using this by changing it in the _config.yml. What do you think?

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