Investigate bug with sanitising of bridge reachability reports
It appears that some bridge reachability reports that are using bridges taken from TBB are being hashed and the bridge_hash_fingeprint and bridge_address are not set.
We should investigate into either removing hashing for TBB reports (leaving the IP PORT in there since they are public) or if figure out why the above keys are not being set.
As an example here is a report that exhibits such problem: http://pipeline.infra.ooni.nu/NL/bridge_reachability-2015-03-05T000013Z-AS47172-probe.yamloo.gz
We probably want to implement this while we are implementing: https://trac.torproject.org/projects/tor/ticket/13638