Twenty Thirteen: minor design tweaks and fixes:

 * Link color should be the same on all links that are on white or tan backgrounds, see #23784
 * Better color value for active menu item (red instead of tan)
 * Improved styles for quote citations that are wrapped in links
 * Better layout for single post navigation links when post titles are '''really''' long
 * Fix navbar border style for viewports at 1600 pixels wide and above

Props Joen and obenland.

git-svn-id: http://core.svn.wordpress.org/trunk@23962 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Twenty Thirteen: improve gallery styles for IE7 and IE8, props kovshenin and obenland. Fixes #23996.

git-svn-id: http://core.svn.wordpress.org/trunk@23963 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Twenty Thirteen: better handling of media in main content area, accounting for a sidebar and all viewport width possibilities. Props sabreuse and obenland, see #23955.

git-svn-id: http://core.svn.wordpress.org/trunk@23964 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Twenty Thirteen: adjust JavaScript handling for scrolling and finding viewport heigh/width to better support various IE versions. Also consolidate variables at the top of the file per best practices. Fixes #23841, props obenland.

git-svn-id: http://core.svn.wordpress.org/trunk@23965 1a063a9b-81f0-0310-95a4-ce76da25c4cd