Add categories to generate_posted_on()

functions.php

if ( ! function_exists( 'generate_posted_on' ) ) :
/**
 * Prints HTML with meta information for the current post-date/time and author.
 */
function generate_posted_on() {

	if ( 'post' !== get_post_type() ) 
		return;
	
	$date = apply_filters( 'generate_post_date', true );
	$author = apply_filters( 'generate_post_author', true );
	$categories = apply_filters( 'generate_show_categories', true );
		
	$time_string = '<time class="entry-date published" datetime="%1$s" itemprop="datePublished">%2$s</time>';
	if ( get_the_time( 'U' ) !== get_the_modified_time( 'U' ) )
		$time_string .= '<time class="updated" datetime="%3$s" itemprop="dateModified">%4$s</time>';

	$time_string = sprintf( $time_string,
		esc_attr( get_the_date( 'c' ) ),
		esc_html( get_the_date() ),
		esc_attr( get_the_modified_date( 'c' ) ),
		esc_html( get_the_modified_date() )
	);
	
	// If our date is enabled, show it
	if ( $date ) :
		printf( '<span class="posted-on">%1$s</span>',
			sprintf( '<a href="%1$s" title="%2$s" rel="bookmark">%3$s</a>',
				esc_url( get_permalink() ),
				esc_attr( get_the_time() ),
				$time_string
			)
		);
	endif;
	
	// If our author is enabled, show it
	if ( $author ) :
		printf( ' <span class="byline">%1$s</span>',
			sprintf( '<span class="author vcard" itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author">%1$s <a class="url fn n" href="%2$s" title="%3$s" rel="author" itemprop="url"><span class="author-name" itemprop="name">%4$s</span></a></span>',
				__( 'by','generate'),
				esc_url( get_author_posts_url( get_the_author_meta( 'ID' ) ) ),
				esc_attr( sprintf( __( 'View all posts by %s', 'generate' ), get_the_author() ) ),
				esc_html( get_the_author() )
			)
		);
	endif;
	
	$categories_list = get_the_category_list( _x( ', ', 'Used between list items, there is a space after the comma.', 'generate' ) );
		if ( $categories_list && $categories ) {
			printf( '<span class="cat-links"><span class="screen-reader-text">%1$s </span>%2$s</span>',
				_x( 'Categories', 'Used before category names.', 'generate' ),
				$categories_list
			);
		}
	
}
endif;