[MERGE] bzr check detects unreferenced revisions

[Robert Collins]

Robert Collins has voted resubmit.
Status is now: Superseded
Comment:
This is a step in the right direction, however I don't think its 
actually correct.

Unreferenced texts are not an issue per se: Hitting ctrl-C during commit 
will cause them in normal operation.

What is a problem is texts which depend on a revision that violates the 
per-file graph only contains nodes in the revision graph rule.
I filed a bug with some details about this 
https://bugs.launchpad.net/bzr/+bug/121509


For details, see: 
http://bundlebuggy.aaronbentley.com/request/%3C46CCA123.2080707%40utoronto.ca%3E