Remove old links_recently_updated_* DB options that never had a UI.

fixes #27649.

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git-svn-id: http://core.svn.wordpress.org/trunk@27746 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Edit Image modal:
- Fix issue with adding a link to an image that didn't have one previously.
- Adjust the look-and-feel of the advance options toggle so that it becomes a section heading that can be open/closed.
- Add a Custom Size option to the size drop-down that reveals fields for soft-resizing the image inserted into the post.
Props gcorne, and props sdasse for the design help, see #27366
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git-svn-id: http://core.svn.wordpress.org/trunk@27748 1a063a9b-81f0-0310-95a4-ce76da25c4cd
TinyMCE:
- Bring back loading of /langs/[locale].js and /langs/[locale]_dlg.js from PHP. Prevents errors with missing translation files when custom plugins use requireLangPack() without second argument.
- Back to using ISO 639-1 (two letter) locales as the locale is used as part of the translation file name.
See #24067, fixes #27610
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git-svn-id: http://core.svn.wordpress.org/trunk@27752 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Database: Add $allow_bail argument to wpdb::check_connection() to match the connect method.

props DrProtocols, pento.
fixes #27240.

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git-svn-id: http://core.svn.wordpress.org/trunk@27755 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Twenty Thirteen and Fourteen: style to support the new HTML5 line-break-less galleries. Props obenland, see #27637.
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git-svn-id: http://core.svn.wordpress.org/trunk@27756 1a063a9b-81f0-0310-95a4-ce76da25c4cd
TinyMCE: update translatable strings, see #27453, #24067
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git-svn-id: http://core.svn.wordpress.org/trunk@27757 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Background Updates: Fix a PHP Warning caused by a Upgrader instance being passed into the Theme & Plugin $extra_stats parameter. See #27633

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git-svn-id: http://core.svn.wordpress.org/trunk@27758 1a063a9b-81f0-0310-95a4-ce76da25c4cd