Error encountered when visiting eclipse

http://projects.eclipse.org/json/projects/all 404's
```
purldb-visitor-1 | INFO:minecode.management.commands.run_visit:Visiting http://projects.eclipse.org/json/projects/all
purldb-visitor-1 | ERROR:minecode.management.commands.run_visit:Visit error for URI: http://projects.eclipse.org/json/projects/all
purldb-visitor-1 | Exception Exception("get_http_response: Download failed for 'http://projects.eclipse.org/json/projects/all' with 404")
purldb-visitor-1 | Traceback (most recent call last):
purldb-visitor-1 | File "/app/minecode/management/commands/run_visit.py", line 255, in visit_uri
purldb-visitor-1 | new_uris_to_visit, visited_data, visit_error = _visit_router.process(uri_to_visit)
purldb-visitor-1 | File "/app/minecode/route.py", line 164, in process
purldb-visitor-1 | return endpoint(string, *args, **kwargs)
purldb-visitor-1 | File "/app/minecode/visitors/__init__.py", line 149, in __call__
purldb-visitor-1 | fetched_content = self.fetch(uri)
purldb-visitor-1 | File "/app/minecode/visitors/eclipse.py", line 140, in fetch
purldb-visitor-1 | return HttpJsonVisitor.fetch(self, uri, timeout=timeout)
purldb-visitor-1 | File "/app/minecode/visitors/__init__.py", line 197, in fetch
purldb-visitor-1 | return fetch_http(uri, timeout=timeout)
purldb-visitor-1 | File "/app/minecode/utils.py", line 214, in fetch_http
purldb-visitor-1 | return get_http_response(uri, timeout).content
purldb-visitor-1 | File "/app/minecode/utils.py", line 236, in get_http_response
purldb-visitor-1 | raise Exception('get_http_response: Download failed for %(uri)r '
purldb-visitor-1 | Exception: get_http_response: Download failed for 'http://projects.eclipse.org/json/projects/all' with 404
```