add support for campaign conversion for shop using api controller
creates a user into mailchimp when an order is sync
put additional test expectation for the auto create users for new orders
lowered spree core version for lesser conflict
Merge branch 'fix/api-compatibility'

* fix/api-compatibility:
  lowered spree core version for lesser conflict
  put additional test expectation for the auto create users for new orders
  add support for campaign conversion for shop using api controller creates a user into mailchimp when an order is sync