Updates to Dashicons classes.

props melchoyce.
fixes #26227.

Built from https://develop.svn.wordpress.org/trunk@26752


git-svn-id: http://core.svn.wordpress.org/trunk@26640 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Themes: Avoid overlap with themes with small screenshots and no description.

props matveb.
fixes #26465.

Built from https://develop.svn.wordpress.org/trunk@26753


git-svn-id: http://core.svn.wordpress.org/trunk@26641 1a063a9b-81f0-0310-95a4-ce76da25c4cd
On the About page: comprise > compromise, assuming that this is a typo. See #26387.


Built from https://develop.svn.wordpress.org/trunk@26754


git-svn-id: http://core.svn.wordpress.org/trunk@26642 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Dashicons: Update to the latest dashicons files.

props empireoflight, melchoyce.
fixes #26362.
Built from https://develop.svn.wordpress.org/trunk@26755


git-svn-id: http://core.svn.wordpress.org/trunk@26643 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Proper CSS specificity for columns-based dashboard grids.

props kovshenin.
fixes #26354.

Built from https://develop.svn.wordpress.org/trunk@26756


git-svn-id: http://core.svn.wordpress.org/trunk@26644 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Twenty Fourteen: Remove stray slash.

props Ipstenu.
fixes #26467.

Built from https://develop.svn.wordpress.org/trunk@26757


git-svn-id: http://core.svn.wordpress.org/trunk@26645 1a063a9b-81f0-0310-95a4-ce76da25c4cd