repost improvements

category_markup in style.php now only sets u-category on person tags and now that u-repost-of markup is handled by Post module only u-url is required when action provided is repost-of. Simplified the way the repost author is passed along in SimplePie->Parser parse_hcard method. Fixed a bug in parse_hcard in microformats.php where nickname and note were being overwritten with empty strings.
core 43 false