Make wp_link_pages() filterable. Add 'separator' argument. Simplify the function logic. props obenland, brianlayman. fixes #13578.

git-svn-id: http://core.svn.wordpress.org/trunk@23653 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Twenty Eleven: set images without WordPress-generated class to 100% maximum width, and fix spacing of images within caption containers. Props obenland, fixes #22366.

git-svn-id: http://core.svn.wordpress.org/trunk@23654 1a063a9b-81f0-0310-95a4-ce76da25c4cd