Set up all auxilliary files needed for a Trelliscope app
prepare_display(base_path, id, self_contained = FALSE, jsonp = TRUE,
pb = NULL)
the base directory of the trelliscope application
a unique id for the application
should the Trelliscope display be a self-contained html document?
should json for display list and app config be jsonp (TRUE) or json (FALSE)?
optional progress bar object to pass in and use to report progress