This is only for the displaying of a folder as a gallery
in either the thumbs, square thumbs, or slideshow.

The allow comments is based on the allowing the folder to have
comments so this means any folder comments will display whether they
have been added following the link in gallery block or the folder
block as both end up at the same artefact on artefact/artefact.php page

Change-Id: I787a730861823ef3f731fb5209bf3470b00a7ed3
Signed-off-by: Robert Lyon <robertl@catalyst.net.nz>