anchor.diff:  `belowRate`:: (float) the lower bound for the request rate metric value. At least one of
   `aboveRate` or `belowRate` must be set.
   
  -`aboveOp`:: collection action to request when the upper threshold for a shard or replica is
  -exceeded. Default action is `ADDREPLICA` and the trigger will request 1 to `maxOps` operations
  -per shard per event, depending how much the rate is exceeded. This property can be set to 'NONE'
  -to effectively disable the action (but still report it to the listeners).
  -
  -`aboveNodeOp`:: collection action to request when the upper threshold for a node is exceeded.
  +`aboveOp`:: (string, optional) collection action to request when the upper threshold for a shard or replica is
  +exceeded. Default action is `ADDREPLICA` and the trigger will request from 1 up to `maxOps` operations
  +per shard per event, proportionally to how much the rate is exceeded. This property can be set to 'NONE'
  +to effectively disable the action but still report it to the listeners.
  +
  +`aboveNodeOp`:: (string, optional) collection action to request when the upper threshold for a node is exceeded.
   Default action is `MOVEREPLICA`, and the trigger will request 1 replica operation per hot node per event.
   If both `aboveOp` and `aboveNodeOp` operations are requested then `aboveNodeOp` operations are
  -always requested first. This property can be set to 'NONE' to effectively disable the action (but still report it to the listeners).
  -
  -`belowOp`:: collection action to request when the lower threshold for a shard or replica is
  +always requested first. This property can be set to 'NONE' to effectively disable the action but still
  +report it to the listeners.
  +
  +`belowOp`:: (string, optional) collection action to request when the lower threshold for a shard or replica is
   exceeded. Default action is `DELETEREPLICA`, and the trigger will request at most `maxOps` replicas
   to be deleted from eligible cold shards. This property can be set to 'NONE'
  -to effectively disable the action (but still report it to the listeners).
  +to effectively disable the action but still report it to the listeners.
   
   `belowNodeOp`:: action to request when the lower threshold for a node is exceeded.
   Default action is null (not set) and the condition is ignored, because in many cases the
  -trigger will monitor only some selected resources (non-pull replica types from selected
  +trigger will monitor only some selected resources (replicas from selected
   collections / shards) so setting this by default to eg. `DELETENODE` could interfere with
   these non-monitored resources. The trigger will request 1 operation per cold node per event.
   If both `belowOp` and `belowNodeOp` operations are requested then `belowOp` operations are
  
positive.code: `nodeAdded` event this will be the time when the node was added and not when the event was actually
  generated, which may significantly differ due to the rate limits set by `waitFor`.
  
  `properties`:: (map, optional) Any additional properties. Currently includes `nodeName` property that
  indicates the node that was lost or added.
  
  == Auto Add Replicas Trigger
  
  
negative.code: * `metric`: generated when the configured metric crosses a configured lower or upper threshold value
  * `indexSize`: generated when a shard size (defined as index size in bytes or number of documents)
  exceeds upper or lower threshold values
  * `searchRate`: generated when the search rate exceeds configured upper or lower thresholds
  * `scheduled`: generated according to a scheduled time period such as every 24 hours etc
  
  Events are not necessarily generated immediately after the corresponding state change occurred - the
  