Lazy loading via GaussHolder functionality

As WordPress provides lazy loading of images by default Altis no longer provides that functionality. See the Lazy Loading announcement for more details.

If you still require the Gaussholder image placeholder functionality, you can add humanmade/Gaussholder to your project.

## Add Gaussholder library
composer require "humanmade/gaussholder"

Then hook into the gaussholder.image_sizes filter.

add_filter( 'gaussholder.image_sizes', function ( $sizes ) {
	$sizes['medium'] = 16;
	$sizes['large'] = 32;
	$sizes['full'] = 84;
	return $sizes;
} );

Note: You can experiment to determine the best sizes (blur radius) to use. See the documentation on Github.