1. ADDED: open_any/3 for recursively opening substreams
          from (1) files (absolute, specification, pattern)
          (2) URIs/URLs (absolute, components), and (3) streams,
          Based on module unpack by Jan Wielemaker.
2. CLEANUP: Removed http_path_correction/2 which is already covered by
           uri_file_name/2 in library(uri).