fix rake task to manually assign shops
Merge pull request #7 from Shopify/fix_assign_manually_rake_task

Fix rake task to manually assign shops
check that Railtie is defined before requiring verdict/railtie
Merge pull request #9 from derekgr/optional_railtie

Check that Railtie is defined before requiring verdict/railtie
add subject_assignment! method
add test for subject_assignment!
update the rake file
Raise an error when manually trying to disqualify someone, but store_unqualified is false for the experiment.
Fix bug in Memory Storage.
Refactor rake tasks, and add tests for them.