message: Handles canceling plan with new endpoint
diff: +Promise = require 'bluebird-q'
  Backbone = require 'backbone'
  template = -> require('./index.jade') arguments...
  @@ -14,13 +15,16 @@ module.exports = class CancelPlanView extends Backbone.View
  $target.text 'Canceling'
  - @model.related().subscription.destroy()
  + Promise $.ajax
  + method: 'POST'
  + url: "#{@model.related().subscriptions.url}/cancel"
  +
  .then =>
  location.reload()
  $target.text 'Canceled'
  - , (error) =>
  + .catch (error) =>
  $target.text label
  @els.errors
  