Allow passing a custom LocalSite to TestCase.create_review_group.
Review Request #5664 — Created April 1, 2014 and submitted
TestCase.create_review_group now accepts a local_site= parameter for
specifying a specific LocalSite to create a Group against. This is being
used in RBCommons, and may be useful down the road in RB.
Used this in RBCommons, and saw was able to successfully make a Group for
a LocalSite.
