Completing333 do not fragment urls

Should solve #333. 

First it generates DO-child *iri*s with a `?` instead of a `#`. This allows the server to handle such
requests as the *child-portion* of the query is actually send to the server.

Secondly it adjusts the handling of urls in `files#files` (`FilesController`),
by checking if there is a query-string and using it to find a child-ontology and
redirecting to it instead of the parent DO.