Will cause a download dialog box to open and prompt user to accept and download the streamed script output. The download will be stored in a folder of their choosing on the local machine either creating or overwriting a file of the specified name.
Parameter: filename(string) Name specification of file on local machine to be created or overwritten.
Note: This header shortcode must always be preceded immediately by the [[HEADER_TYPE]] shortcode which is the first command in the index or body template.. This is because all header modifying commands must be placed or poked in to the active index template as specified at the top of body.tpl.