Added for the next build.
INCLUDEONLY wraps portions of the template that are only displayed when it's included in another page.
NOINCLUDE wraps portions of the template that are only displayed on the Template page.
Portions that are wrapped by neither will be displayed on both. As in previous versions, these portions will not show parsed on the Template page.
In theory, it should now be possible to categorize Templates separately from pages that include those templates. Using these new template features, you can easily write usage instructions on the Template page without worrying about its inclusion in other pages.