Code review comment for lp:~lifeless/bzr/subunit

I'm proposing this branch to get feedback; its not necessarily ripe, though I'd be happy to land it as-is (there aren't any must-do items remaining for it).

This branch deletes a bunch of code:
 17 files changed, 180 insertions(+), 350 deletions(-)

It dos this by using testtools as a base class and using the defined extension points there to add bzr specific functionality.

The net effect of doing this:
 - bzr selftest --parallel will now show log files, as will --subunit and pqm if we enable subunit there again.
 - assertThat is available for bzr to use
 - bzr no longer needs an implementation of run(), addCleanup(). There may be more duplicate assertions, but I haven't been on a hunt to minimise the duplication.

testtools 0.10 will be needed (that isn't released yet, but jml wants to bump to -10 when we make run() extensible. I'm putting a branch for that up for review in a few minutes).

-Rob