Cleanup audio/video shortcodes in the media modal:

* On the controller's `update`, `replace`, and `close` events, call `detach()` on the frame
* Cleanup the HTML ouput of the Underscore templates.
* Move some logic from the Underscore template to the `VideoDetails` view class.

See #27016.


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git-svn-id: http://core.svn.wordpress.org/trunk@27287 1a063a9b-81f0-0310-95a4-ce76da25c4cd
maybe_regenerate_attachment_metadata() is now wp_maybe_generate_attachment_metadata().

props kovshenin.
fixes #26825.

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git-svn-id: http://core.svn.wordpress.org/trunk@27288 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Twenty Fourteen: Add a .button class.

props celloexpressions.
fixes #27075.

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git-svn-id: http://core.svn.wordpress.org/trunk@27289 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Call the correct `remove()` method on the MEjs instance when exiting the media modal.

See #27016.


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git-svn-id: http://core.svn.wordpress.org/trunk@27290 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Add missing Dashicons classes to Network Admin menu, see #26630.
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git-svn-id: http://core.svn.wordpress.org/trunk@27291 1a063a9b-81f0-0310-95a4-ce76da25c4cd
At long last, a first pass at bringing the image editor into the media modal. props gcorne, DH-Shredder, tomauger. see #21811.

Built from https://develop.svn.wordpress.org/trunk@27445


git-svn-id: http://core.svn.wordpress.org/trunk@27292 1a063a9b-81f0-0310-95a4-ce76da25c4cd