anchor.diff:  
   |periodTimeUnit
   |Yes
  -|Time unit ("SECONDS", "MINUTES" )
  +|Time unit (`SECONDS`, `MINUTES`)
   |String
   |SECONDS
   
   |===
   
  +==== Configuration example
   
   [source, json]
  -.Sample
   ----
     "spike": {
       "limit": "10",
  
positive.code: 
  == Description
  
  There are three rate limit policies:
  
  * Quota: configure the number of requests allowed over a period of time (Hours, Days, Weeks, Months)
  * Rate-Limit: configure the number of requests allowed over a limited period of time ( Seconds, Minutes)
  * Spike-Arrest: throttle the number of requests processed and send to the backend to avoid spike
  
  == Configuration
  
  You can configure the policy with the following options :
  
  === Quota
  
  Quota Policy configures the number of requests allow over an important period of time (from Hour to Month).
  This policy doesn't prevent from spike of request.
  
  |===
  |Property |Required |Description |Type |Default
  
  |key
  |No
  |Key to identify a consumer against whom the quota will be applied. Leave it empty to use the default behavior (plan/subscription pair). Supports EL.
  |String
  |null
  
  
negative.code: 
  === Rate-Limit
  
  The Rate-Limit policy configures the number of requests allow over a limited period of time (from seconds to minutes).
  This policy does not prevent request spikes.
  
  |===
  |Property |Required |Description |Type |Default
  
  |key
  |No
  |Key to identify a consumer to apply rate-limiting against. Leave it empty to use the default behavior (plan/subscription pair). Supports Expression Language.
  |String
  |null
  
  