VE-1207: Focus mode adjustments for Category namespace

https://wikia-inc.atlassian.net/browse/VE-1207
var $this = $( this );
return !( 
	// Category thumbs
	$this.hasClass( 'category-gallery' ) ||
	// Category exhibition
	$this.is( '#mw-pages' ) ||
	// Category list
	$this.children( '#mw-pages' ).length === 1
);