Twenty Fifteen: correct styles for color schemes

Props iamtakashi, fixes #29976.


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git-svn-id: http://core.svn.wordpress.org/trunk@29717 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Twenty Fifteen: beautify the header in IE 8.

Props afercia, fixes #30042.


Built from https://develop.svn.wordpress.org/trunk@29972


git-svn-id: http://core.svn.wordpress.org/trunk@29718 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Twenty Fifteen: correct button sizes.

Props iamtakashi, fixes #30045.


Built from https://develop.svn.wordpress.org/trunk@29973


git-svn-id: http://core.svn.wordpress.org/trunk@29719 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Twenty Fifteen: correct comment meta alignment when avatar display is turned off.

Props iamtakashi, fixes #30046.


Built from https://develop.svn.wordpress.org/trunk@29974


git-svn-id: http://core.svn.wordpress.org/trunk@29720 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Twenty Fifteen: Adding in the twentyfifteen credits action.

Props iamtakashi, fixes #30051.


Built from https://develop.svn.wordpress.org/trunk@29975


git-svn-id: http://core.svn.wordpress.org/trunk@29721 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Twenty Fifteen: updated styles for skip link.

Props afercia and iamtakashi, fixes #30043.


Built from https://develop.svn.wordpress.org/trunk@29976


git-svn-id: http://core.svn.wordpress.org/trunk@29722 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Fix copy/paste errors in [27769].

props Corphi.
fixes #30054.
Built from https://develop.svn.wordpress.org/trunk@29977


git-svn-id: http://core.svn.wordpress.org/trunk@29723 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Admin menu:
- Fix scrolling the pinned menu with a mouse wheel.
- Fix pinning when the menu is only slightly taller than the viewport.
- Disable pinning on IE8, updating CSS top makes it jump when scrolling with a mouse wheel.
See #29806
Built from https://develop.svn.wordpress.org/trunk@29978


git-svn-id: http://core.svn.wordpress.org/trunk@29724 1a063a9b-81f0-0310-95a4-ce76da25c4cd