anchor.diff:  By default, new version must be backward compatible which means that a consumer should be able to deal with an event flagged with an older version.
   
   Version format follows the http://semver.org[semver] protocol.
  +
  +=== snapshot
  +
  +The `snapshot` field indicates if the `version` is under development.
  +Snapshots are not always backward compatible, an the backend will never send snapshot documents when the application version is a release.
  +Therefore, `snapshot` will be always `false` in production.
   
   === event 
   
  
positive.code:     {
  		    "topic" : "organization|user|artifact"
  		    "version" : "...",
  		    "event" : "...",
  		    "data" : "...",
  		    "timestamp" : "...",
  
negative.code: The `ADD_CATEGORY_ITEM`, `READ_CATEGORY_CATEGORY` and `UPDATE_CATEGORY_ITEM` events for an `Organization` have a `data` attribute associated to a value that looks like this:
  
      {
          "category": "The category ID"
          "name" : "The name of the item"
          "picture" : "The picture of the item"
      }
  