Twenty Thirteen: change Genericon element display to `inline-block` to avoid underlining the icon when its related element wrapped in a link. Props obenland, fixes #24045.

git-svn-id: http://core.svn.wordpress.org/trunk@23966 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Twenty Thirteen: improve comment label selectors and nudge up their width a bit to account for non-English installs. Props obenland for initial patch, fixes #24039.

git-svn-id: http://core.svn.wordpress.org/trunk@23967 1a063a9b-81f0-0310-95a4-ce76da25c4cd