[MERGE] Allow addCleanup to take arguments

[Andrew Bennetts]

Jonathan Lange wrote:
> Hello all,
> 
> This patch allows addCleanup to take arguments and removes the
> uniqueness check from addCleanup. This brings addCleanup more inline
> with the implementations in Twisted, Launchpad and pyunit3k and also
> more in line with the advice I received from Robert and Martin when I
> wrote those implementations. <wink>
> 
> This patch doesn't add tests for addCleanup, seeing as none were there
> — it's just a quick fix to make my life easier. If you'd like tests, I
> guess I could pinch some from https://launchpad.net/pyunit3k.

bb:approve

It would be nice to have tests for this.  I guess ultimately reusing pyunit3k in
bzrlib might be the way to do that, rather than having independent
implementations of the same thing.

-Andrew.