anchor.diff:  --------------------------------------------------
   // TESTRESPONSE[s/\.\.\./"took": $body.took,"timed_out": false,"_shards": $body._shards,"hits": $body.hits,/]
   
  -The response will contain all the buckets having as key the relative day of
  -the week: 1 for Monday, 2 for Tuesday... 7 for Sunday.
  +The response will contain all the buckets having the relative day of
  +the week as key : 1 for Monday, 2 for Tuesday... 7 for Sunday.
  
positive.code: --------------------------------------------------
  // TESTRESPONSE[s/\.\.\./"took": $body.took,"timed_out": false,"_shards": $body._shards,"hits": $body.hits,/]
  
  ==== Time Zone
  
  Date-times are stored in Elasticsearch in UTC.  By default, all bucketing and
  rounding is also done in UTC. The `time_zone` parameter can be used to indicate
  that bucketing should use a different time zone.
  
  Time zones may either be specified as an ISO 8601 UTC offset (e.g. `+01:00` or
  `-08:00`)  or as a timezone id, an identifier used in the TZ database like
  `America/Los_Angeles`.
  
  Consider the following example:
  
  
negative.code: // TESTRESPONSE[s/\.\.\./"took": $body.took,"timed_out": false,"_shards": $body._shards,"hits": $body.hits,/]
  
  <1> The `key_as_string` value represents midnight on each day
      in the specified timezone.
  
  WARNING: When using time zones that follow DST (daylight savings time) changes,
  buckets close to the moment when those changes happen can have slightly different
  sizes than you would expect from the used `interval`.
  For example, consider a DST start in the `CET` time zone: on 27 March 2016 at 2am,
  clocks were turned forward 1 hour to 3am local time. If you use `day` as `interval`,
  the bucket covering that day will only hold data for 23 hours instead of the usual
  24 hours for other buckets. The same is true for shorter intervals, like 12h,
  where you'll have only a 11h bucket on the morning of 27 March when the DST shift
  happens.
  
  ===== Offset
  
  Use the `offset` parameter to change the start value of each bucket by the
  specified positive (`+`) or negative offset (`-`) duration, such as `1h` for
  an hour, or `1d` for a day. See <<time-units>> for more possible time
  duration options.
  
  For example, when using an interval of `day`, each bucket runs from midnight
  to midnight.  Setting the `offset` parameter to `+6h` changes each bucket
  to run from 6am to 6am:
  
  [source,js]
  