* Add PlanSponsorshipType to static store
* Add sponsorship type to token and creates sponsorship
* PascalCase properties
* Require sponsorship for remove
* Create subscription sponsorship helper class
* Handle Sponsored subscription changes
* Add sponsorship id to subscription metadata
* Make sponsoring references nullable
This state indicates that a sponsorship has lapsed, but was not able to
be reverted for billing reasons
* WIP: Validate and remove subscriptions
* Update sponsorships on organization and org user delete
* Add friendly name to organization sponsorship