Each source can also have other files attached. Anything that is not
the main content file in a folder is considered to be an attachment.
There are a few settings to control these in the
enabled: if set to
nothen attachments are disabled. If they do exist in the folder they are silently ignored.
model: an optional default model that is used for all attachments.
order_by: controls the ordering of attachments, similar to how this works for child pages.
hidden: if this is set it can override the hidden flag for all attachments at once. The default as of Lektor 2 is that attachments are not hidden by default.
hidden flag was added in Lektor 2.0 and the default was changed so
that attachments are not hidden by default, even if the parent is.