BzrSvn: Make bzr-svn more resilient to failures of commands.
Add some tests for the lint steps.
Refactor some code.
Add a bunch of tests for computeDifference.
Add a bunch of docstrings.
Add a force scheduler for building benchmarks.
Stop using custom 'unschedule' key for builders.

Instead, assign a different category to those builders.
Refactor a bit of code, to make test deployment easier.
Move (silent) IRC bot to #twisted-dev.
Fix boxes pages to not get displayed via the __repr__ of a Deferred.
Only allow force building benchmarks on trunk.
fix typos.
Add support to twistedchecker for only checking a specific subtree.
Add some tests for actual lint steps.
Factor out dealing with logs, from the acquisition of logs.
Make twistedchecker split errors by toplevel module.
Use stdio log, instead to get results from previous build.

With twisted checker splitting up errors, the expected old log doesn't exist.
Put all errors after the new errors, in twistedchecker.
Split up twistedchecker errors by toplevel module.
Fix stupid typo.