[MERGE] Fix for 306394: warning, not error, on non-existent file.

[Ian Clatworthy]

Ian Clatworthy has voted resubmit.
Status is now: Resubmit
Comment:
As discussed on the mailing list, I think non-existence needs to be 
reported on standard output like any other file status. It may also be 
useful to return a non-zero exit code (2 is suggested) if non-existent 
files are detected.

For details, see: 
http://bundlebuggy.aaronbentley.com/project/bzr/request/%3C87zlimo7l5.fsf%40canonical.com%3E
Project: Bazaar