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.


git-svn-id: https://develop.svn.wordpress.org/trunk@28993 602fd350-edb4-49c9-b593-d223f7449a82
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.

git-svn-id: https://develop.svn.wordpress.org/trunk@28994 602fd350-edb4-49c9-b593-d223f7449a82
Make media grid text fields (data) toggle-able. Checking/unchecking is saved in user settings cookie.

See #24716.


git-svn-id: https://develop.svn.wordpress.org/trunk@28995 602fd350-edb4-49c9-b593-d223f7449a82
Media Grid: for audio and video files with covers, show that instead of the icon. The filename is still present with the extension to identify the type.

See #24716.


git-svn-id: https://develop.svn.wordpress.org/trunk@28996 602fd350-edb4-49c9-b593-d223f7449a82
Media Grid: Use the proper attachment value for `uploadedToTitle`.

See #24716.


git-svn-id: https://develop.svn.wordpress.org/trunk@28997 602fd350-edb4-49c9-b593-d223f7449a82
Media Grid: JSHint fixes.

See #24716. 


git-svn-id: https://develop.svn.wordpress.org/trunk@28998 602fd350-edb4-49c9-b593-d223f7449a82
Add is_customize_preview(), a conditional function to check if the site is being previewed in the Customizer.

props sammybeats, mattwiebe.
fixes #23509.

git-svn-id: https://develop.svn.wordpress.org/trunk@28999 602fd350-edb4-49c9-b593-d223f7449a82
Fix a regression of positioning in Attachment Display Settings.

props paulwilde.
see #24716.

git-svn-id: https://develop.svn.wordpress.org/trunk@29000 602fd350-edb4-49c9-b593-d223f7449a82
Fix alignment of Advanced Options close toggle arrow in Edit Media dialog.

props paulwilde.
fixes #28752.

git-svn-id: https://develop.svn.wordpress.org/trunk@29001 602fd350-edb4-49c9-b593-d223f7449a82
Reinstate 'install_themes_tabs' filter.

props ghost1227.
fixes #28578.

git-svn-id: https://develop.svn.wordpress.org/trunk@29002 602fd350-edb4-49c9-b593-d223f7449a82
Add 'status-sticky' class in get_post_class() for sticky posts in the admin.

props mordauk, netweb.
fixes #22590.

git-svn-id: https://develop.svn.wordpress.org/trunk@29003 602fd350-edb4-49c9-b593-d223f7449a82
Remove debug remnants, see #28595

git-svn-id: https://develop.svn.wordpress.org/trunk@29004 602fd350-edb4-49c9-b593-d223f7449a82
Don't include plugin.php twice in setup-config.php.

fixes #28744. see #28740, [28978].


git-svn-id: https://develop.svn.wordpress.org/trunk@29005 602fd350-edb4-49c9-b593-d223f7449a82
Bring the language chooser to setup-config.php.

see #28577.


git-svn-id: https://develop.svn.wordpress.org/trunk@29006 602fd350-edb4-49c9-b593-d223f7449a82
Introduce wp_dropdown_languages() and use it on general settings.

Early rough cut. Obviously not fully implemented.

see #15677.


git-svn-id: https://develop.svn.wordpress.org/trunk@29007 602fd350-edb4-49c9-b593-d223f7449a82
Merge branch 'master' of git://develop.git.wordpress.org