Twenty Thirteen: second pass at styles for attachment pages that are not images: hide sidebar and navigation link, better alignment of Edit link.

Closes #23632.

git-svn-id: http://core.svn.wordpress.org/trunk@23544 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Twenty Thirteen: fix missing space in selector! Props markmcwilliams, fixes #23652.

git-svn-id: http://core.svn.wordpress.org/trunk@23545 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Twenty Thirteen: trim down font properties, props obenland. Fixes #23546.

git-svn-id: http://core.svn.wordpress.org/trunk@23546 1a063a9b-81f0-0310-95a4-ce76da25c4cd