Category Hierarchy in Jekyll <p>I've been trying to use Jekyll categories in a hierarchical fashion, i.e.</p> <pre><code>A: ['class', 'topic', 'foo'] AA: ['class', 'topic', 'foo', 'bar'] AB: ['class', 'topic', 'foo', 'baz'] AAA: ['class', 'topic', 'foo', 'bar', 'qux'] </code></pre> <p>I'm trying to create a listing of all immediate subdirectories programmatically. That is, on a page with categories (A), I wish to be able to list the posts with categories (AA) and (AB), but not (AAA). Is this possible with Jekyll's vanilla structure, or should I consider using a plugin?</p>