Prepares the attachment directories for being displayed in the list.

Return value

Expected type: Array of arrays
Description: An array containing arrays of information about each attachment directory

• Gets the attachment directories from $modSettings['attachmentUploadDir']
• Calls attachDirStatus to check the status of each directory
• Returns an array of arrays, with each array containing information about an individual directory
• Each array in the returned array has the following keys: id (internal folder ID), current (whether or not this is the directory specified in $modSettings['currentAttachmentUploadDir']), path (path to the directory), current_size (size of all files in the directory), num_files (how many files SMF thinks are in the directory) and status (see attachDirStatus)