Media grid, round 2. Expect much more to come.

* Instead of a sidebar for details, utilize a modal. The modal experience allows for a larger preview, editing images, audio/video previews, and previous/next navigation, like the theme browser. Think of it as an attachment browser.
* Show some details in the grid view to more easily distinguish items.

props ericlewis, wonderboymusic, JerrySarcastic. see #24716.

Built from https://develop.svn.wordpress.org/trunk@28993


git-svn-id: http://core.svn.wordpress.org/trunk@28781 1a063a9b-81f0-0310-95a4-ce76da25c4cd
TinyMCE: improve the way wpViews work. Add two paragraphs and capture the caret in them on clicking before/after/left/right of a view or moving the caret with the arrow keys, then show a "fake" caret.

This makes it much more "natural" to move the caret with the arrow keys and to add paragraphs before a view when it is the first element or after a view when it's last.

Props avryl, see #28595.
Built from https://develop.svn.wordpress.org/trunk@28994


git-svn-id: http://core.svn.wordpress.org/trunk@28782 1a063a9b-81f0-0310-95a4-ce76da25c4cd