Add method to tiers for optgroups (bugs 882831, 882836)
Merge pull request #811 from muffinresearch/add-method-to-tiers

Add method to tiers for optgroups (bugs 882831, 882836)
add management command to load price data
add CORSViewSet for CORS enabled DRF views
fix logo wrapping (bug 883879)
Allow reviewers to override minimum requirements for an app (bug 862467)
Make features profile changes trigger re-review (bug 862449)