add var_expired_by(time)

@@ -202,6 +202,10 @@ module ActsAsChargeable
       clean_var_variables
     end
 
+    def var_expired_by(time)
+      return var_payment_expires_at + time < Time.zone.now && !var_payed?
+    end
+
     private
 
     def clean_var_variables

 # Var Version
 module Var
-  VERSION = '0.2.20'
+  VERSION = '0.2.21'
 end