[MERGE] Improve "Path(s) are not versioned" error reporting for some commands

[Ian Clatworthy]

Ian Clatworthy has voted tweak.
Status is now: Conditionally approved
Comment:
I'll add a NEWS entry and merge.

For details, see: 
http://bundlebuggy.aaronbentley.com/project/bzr/request/%3C20090624230503.GA21965%40localdomain%3E
Project: Bazaar