Function image_candidates 

pub fn image_candidates(path: &str) -> String

Perl: image_candidates($path) (Util::Image L43-57).

Returns comma-separated list of candidate paths for path, searching GRAPHICSPATHS + SEARCHPATHS + SOURCEDIRECTORY. Paths are returned relative to SOURCEDIRECTORY when possible, matching the Perl pathname_relative($_, $base) post-filter.