This interface is used to receive contents of directory index listings
from a protocol. They can then be transformed into an output format
(such as rdf, html, etc)
Called for each directory entry
| request | - the request |
| ctxt | - opaque parameter |
| index | - new index to add |
Called for each information line
| request | - the request |
| ctxt | - opaque parameter |
| info | - new info to add |