Code review comment for lp:~gary/launchpad/refactoractivitylog

This branch looks good. It's a mostly mechanical translation with a
nice addition to documentation/testing. Approved* (*Brad will have to
review my review.)

One small thing I noticed: in lib/lp/bugs/interfaces/bugactivity.py the
description arguments of the two moved attributes (target and attribute)
use different quotes (single vs. double) and indentation (just 4 spaces
for target and fancy indentation for attribute).