Move CronoJob to models dir

app/models/crono/application_record.rb

@@ -0,0 +1,5 @@
+module Crono
+  class ApplicationRecord < ActiveRecord::Base
+    self.abstract_class = true
+  end
+end

app/models/crono/crono_job.rb

@@ -1,5 +1,3 @@
-require 'active_record'
-
 module Crono
   # Crono::CronoJob is a ActiveRecord model to store job state
   class CronoJob < ActiveRecord::Base

lib/crono.rb

@@ -15,5 +15,4 @@ require 'crono/scheduler'
 require 'crono/config'
 require 'crono/performer_proxy'
 require 'crono/cronotab'
-require 'crono/orm/active_record/crono_job'
 require 'crono/railtie' if defined?(Rails)