CBD-1412: add revAB_sim modules to the project

+ minor changes in order to pass flake8

Execution:
python -m perfrunner.workloads.revAB

Change-Id: Ie53fba09d3aac75c756218c9fef362cb488b951f
Reviewed-on: http://review.couchbase.org/39994
Tested-by: buildbot <build@couchbase.com>
Reviewed-by: Dave Rigby <daver@couchbase.com>