In `WP_Meta_Query`, interpret 'value' correctly when used with EXISTS/NOT EXISTS.

As in earlier versions, EXISTS with a value is equivalent to '=', while NOT
EXISTS should always ignore 'value'.

Merges [30846] to the 4.1 branch.

Props barrykooij.
Fixes #30681

Built from https://develop.svn.wordpress.org/branches/4.1@30848


git-svn-id: http://core.svn.wordpress.org/branches/4.1@30838 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Improve text for the DFW admin pointer. Remove the concatenation.
Props kpdesign, ianmjones.

Merges [30837] to the 4.1 branch.

See #30671.

Built from https://develop.svn.wordpress.org/branches/4.1@30850


git-svn-id: http://core.svn.wordpress.org/branches/4.1@30840 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Revisions: Fix initial state of `compareTwoMode`.

Merges [30831] to the 4.1 branch.

Fixes #30672.

Built from https://develop.svn.wordpress.org/branches/4.1@30851


git-svn-id: http://core.svn.wordpress.org/branches/4.1@30841 1a063a9b-81f0-0310-95a4-ce76da25c4cd
About page updates.
 * Live-update the number of active translations.
 * Finalize most strings.
 * Lazily remove links to admin-only screens based on cap checks.

Merges [30840] and [30841] to the 4.1 branch.

see #30435.

Built from https://develop.svn.wordpress.org/branches/4.1@30858


git-svn-id: http://core.svn.wordpress.org/branches/4.1@30848 1a063a9b-81f0-0310-95a4-ce76da25c4cd
About page design for 4.1.

Merges [30857] to the 4.1 branch.

props melchoyce and ryelle, who again outdid themselves.
see #30435.

Built from https://develop.svn.wordpress.org/branches/4.1@30859


git-svn-id: http://core.svn.wordpress.org/branches/4.1@30849 1a063a9b-81f0-0310-95a4-ce76da25c4cd
TinyMCE: make the tooltip for the remove button in the image toolbar translatable.

Merges [30835] to the 4.1 branch.

Props pavelevap
Fixes #30694

Built from https://develop.svn.wordpress.org/branches/4.1@30861


git-svn-id: http://core.svn.wordpress.org/branches/4.1@30851 1a063a9b-81f0-0310-95a4-ce76da25c4cd
TinyMCE: add another `Edit` translatable string for the tooltip of the Edit button on the image toolbar.

Merges [30839] to the 4.1 branch.

Props pavelevap
Fixes #30694

Built from https://develop.svn.wordpress.org/branches/4.1@30862


git-svn-id: http://core.svn.wordpress.org/branches/4.1@30852 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Customizer: Don't escape control descriptions in JavaScript templates.

Merges [30847] to the 4.1 branch.

Fixes #30682.

Built from https://develop.svn.wordpress.org/branches/4.1@30863


git-svn-id: http://core.svn.wordpress.org/branches/4.1@30853 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Avoid repeatedly calling is_tax( 'post_format', '...' ) in get_the_archive_title().

Merges [30854] to the 4.1 branch.

See #21995.

Built from https://develop.svn.wordpress.org/branches/4.1@30864


git-svn-id: http://core.svn.wordpress.org/branches/4.1@30854 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Rename _wp_clear_update_cache() to wp_clean_update_cache().

This makes it match most cache-clearing functions, including the ones it wraps. Also no need for it to be prefixed as "private."

wp_clean_plugins_cache() doesn't always exist, so as a quick fix, clear the transient we care to clear.

Merges [30856] to the 4.1 branch.

Fixes #30369.

Built from https://develop.svn.wordpress.org/branches/4.1@30870


git-svn-id: http://core.svn.wordpress.org/branches/4.1@30860 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Clarify the behaviour of the `wp_editor_set_quality` and `jpeg_quality` filters.

Merges [30874] to the 4.1 branch.

Props DH-Shredder
See #29856

Built from https://develop.svn.wordpress.org/branches/4.1@30876


git-svn-id: http://core.svn.wordpress.org/branches/4.1@30864 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Twenty Fifteen: remove license details for the image shown in the theme  screenshot file as it is Creative Commons Zero, which doesn't require attribution.

Merges [30867] to the 4.1 branch.

Props iamtakashi
See #30156

Built from https://develop.svn.wordpress.org/branches/4.1@30877


git-svn-id: http://core.svn.wordpress.org/branches/4.1@30865 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Fix search box position on the Add Plugins screen after resizing the window to narrower than 1000px and then back to wider than 1200px.

Merges [30830] to the 4.1 branch.

Fixes #30658.

Built from https://develop.svn.wordpress.org/branches/4.1@30878


git-svn-id: http://core.svn.wordpress.org/branches/4.1@30866 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Correct the height of the search type `select` element when searching the plugin directory.

Merges [30879] to the 4.1 branch.

Fixes #30719
Props pavelevap, eliorivero

Built from https://develop.svn.wordpress.org/branches/4.1@30880


git-svn-id: http://core.svn.wordpress.org/branches/4.1@30868 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Twenty Fifteen: remove fonts as a style dependency.

Merges [30832] to the 4.1 branch.

Props obenland, SergeyBiryukov.
Fixes #30678.

Built from https://develop.svn.wordpress.org/branches/4.1@30881


git-svn-id: http://core.svn.wordpress.org/branches/4.1@30869 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Twenty Fifteen: remove Genericons as a dependency from loading the main stylesheet.

Merges [30865] to the 4.1 branch.

Props iamtakashi
See #30532.

Built from https://develop.svn.wordpress.org/branches/4.1@30882


git-svn-id: http://core.svn.wordpress.org/branches/4.1@30870 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Twenty Fourteen: remove Genericons as a dependency from loading the main stylesheet and IE-specific stylesheet.

Merges [30866] to the 4.1 branch.

See #30532.

Built from https://develop.svn.wordpress.org/branches/4.1@30883


git-svn-id: http://core.svn.wordpress.org/branches/4.1@30871 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Update Akismet external to 3.0.4 in the 4.1 branch.


git-svn-id: http://core.svn.wordpress.org/branches/4.1@30875 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Call it 'Distraction-free writing mode' and update the help string.

Merges [30890] to the 4.1 branch.

Fixes #30657.

Built from https://develop.svn.wordpress.org/branches/4.1@30892


git-svn-id: http://core.svn.wordpress.org/branches/4.1@30882 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Finalize two more about page strings.

Merges [30887] to the 4.1 branch.

See #30435

Built from https://develop.svn.wordpress.org/branches/4.1@30894


git-svn-id: http://core.svn.wordpress.org/branches/4.1@30884 1a063a9b-81f0-0310-95a4-ce76da25c4cd