Update help content for Dashboard. props kpdesign. fixes #26632.
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git-svn-id: http://core.svn.wordpress.org/trunk@26917 1a063a9b-81f0-0310-95a4-ce76da25c4cd
TinyMCE: add dashicon for the "wp_page" button, see #24067.
Built from https://develop.svn.wordpress.org/trunk@27044


git-svn-id: http://core.svn.wordpress.org/trunk@26918 1a063a9b-81f0-0310-95a4-ce76da25c4cd