add data to Cron.perform which will be passed to ExampleJob.new(data).perform

lib/generators/crono/install/templates/migrations/create_crono_jobs.rb

@@ -5,6 +5,7 @@ class CreateCronoJobs < ActiveRecord::Migration
       t.text      :log
       t.datetime  :last_performed_at
       t.boolean   :healthy
+      t.text      :data
       t.timestamps null: false
     end
     add_index :crono_jobs, [:job_id], unique: true