Basic SMS and email adapters. Campaign moved to a subclass of CampaignTemplate, as it shares almost all of its properties
Add Liquid validation of template syntax
Pre-render templates with the sender, for things like booking links and logos
Add template destroy route
Remove nulls on bool column so default values work
Add base controller class config option to allow complex custom auth
Support scheduling delivery. Filters recipients when scheduled, rather than when sent. Sending and filtering happens on Sidekiq workers