Eugen Rochko 7dc5035031 Make PreviewCard records reuseable between statuses ()
* Make PreviewCard records reuseable between statuses

**Warning!** Migration truncates preview_cards tablec

* Allow a wider thumbnail for link preview, display it in horizontal layout ()

* Delete preview cards files before truncating

* Rename old table instead of truncating it

* Add mastodon:maintenance:remove_deprecated_preview_cards

* Ignore deprecated_preview_cards in schema definition

* Fix null behaviour
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v1 Make PreviewCard records reuseable between statuses ()
web Embed modal ()
base_controller.rb Don't send Link header when don't know prev and next links ()
oembed_controller.rb Update status embeds ()
push_controller.rb Fix - Connect signed PuSH subscription requests to instance domain ()
salmon_controller.rb Clean up for api/base controller ()
subscriptions_controller.rb HTTP signatures ()