A singleton object of this class is used to deal with attachments to topics.
Constructor.
Generate a table of attachments suitable for the bottom of a topic view, using templates for the header, footer and each row.
$web the web
$topic the topic
$meta meta-data hash for the topic
$args hash of attachment arguments
Generate a version history table for a single attachment
$web - the web
$topic - the topic
$attrs - Hash of meta-data attributes
$user - User doing the reading
$web - Name of the web
$topic - Name of the topic
$name - Name of the attachment
$meta - Meta object that contains the meta info
Build a link to the attachment, suitable for insertion in the topic.