Code review comment for lp://staging/~zomux/twisted-buildbot-configuration/add-builder-twistedchecker

The buildstep is pretty much a copy&paste from the documentation checker. The code should really be factored out into a common base class.

Probably both createSummary and getPreviousLog can be moved to the base class, and use a class attribute to specify which log file to grab.

Sorry for taking so long to get to this, it arrived when I had almost no review bandwidth.

I'll do the refactoring eventually, if somebody else doesn't get there first.