Set up site to use new WordPress image sizes

WordPress is adding new image sizes in version 5.3, so our custom image
size is redundant. Keeping it in for back compat, plus older images
will still need to be retrieved using the old image size name, or else
the original size will be used in lieu of a correctly sized option.

includes/meta/class-displayfeaturedimagegenesis-postmeta.php

@@ -131,8 +131,8 @@ class Display_Featured_Image_Genesis_Post_Meta {
 		$image_sizes = apply_filters(
 			'displayfeaturedimagegenesis_image_size_choices',
 			array(
-				'displayfeaturedimage_backstretch' => __( 'Use a banner image if it exists', 'display-featured-image-genesis' ),
-				'large'                            => __( 'Use a large (not banner) image', 'display-featured-image-genesis' ),
+				'banner' => __( 'Use a banner image if it exists', 'display-featured-image-genesis' ),
+				'large'  => __( 'Use a large (not banner) image', 'display-featured-image-genesis' ),
 			)
 		);
 
@@ -174,12 +174,14 @@ class Display_Featured_Image_Genesis_Post_Meta {
 	 */
 	protected function do_select( $args, $post_id ) {
 		$value  = get_post_meta( $post_id, $args['setting'], true );
-		$output = sprintf( '<p>%1$s<select id="%2$s" name="%2$s">',
+		$output = sprintf(
+			'<p>%1$s<select id="%2$s" name="%2$s">',
 			esc_attr( $args['label'] ),
 			esc_attr( $args['setting'] )
 		);
 		foreach ( (array) $args['options'] as $option => $field_label ) {
-			$output .= sprintf( '<option value="%s" %s>%s</option>',
+			$output .= sprintf(
+				'<option value="%s" %s>%s</option>',
 				esc_attr( $option ),
 				selected( $option, $value, false ),
 				esc_attr( $field_label )