[MERGE] the -Devil is in the details

[Martin Pool]

Martin Pool has voted approve.
Status is now: Approved
Comment:
For background, we decided not to turn this on by default because most 
people running Bazaar won't be in a position to do anything about most 
of these problems, so we won't want to show warnings always.

If it's really so evil, maybe it should be written to stderr rather than 
just to the log?  Still, this looks good to start with.

>if evil in debug.debug_options:
>    mutter_callsite(1, "Foo-bar was called with %s %s", arg1, arg2)

There should be quotes around the second word there.

For details, see: 
http://bundlebuggy.aaronbentley.com/request/%3C1187582364.4150.115.camel%40localhost.localdomain%3E