This prevents the crawler to descent into the wiki directory or data
directory, even when for some reason a higher up directory was made
accessible. This should prevent the circumvention of ACLs and prevent
access to sensitive data like user password hashes etc.
This refactors the plugin from one mega syntax file into multiple
classes.
The plugin now focuses on one usecase: listing files that are external
to the wiki and making them downloadable. All other usecases have been
dropped. Also a bunch of other options have been dropped.
A new dispatcher makes it possible to deliver files without the need to
have the webserver pointing at them.
