Add byline
use WP HTML5 markup for captions instead of Soil

Use add_theme_support to enable native HTML5 captions and add caption styling to wp-caption-text.
Merge pull request #1105 from kevinlisota/html5-captions

use WP HTML5 markup for captions instead of Soil
Remove unnecessary string concatenation.
Merge remote-tracking branch 'upstream/master'
Merge branch 'master' into modular