anchor.diff:  Additional attributes when `type = 'table'`.
   
       {
  -        "columns" : "Category enumerating the columns",
  -        "rows" : "Category enumerating the rows"
  +        "columns" : "Category id enumerating the columns",
  +        "rows" : "Category id enumerating the rows"
       }
   
   * `columns`: a category `id` containing the values displayed in column titles. `Artifact` will be organized vertically according to the value of this category. This value is mandatory.
  
positive.code: In fact, the event simply indicates that an `Organization` identified by the event `id` has been deleted.
  Therefore, no more information than the `id` is required to identify the removed `Organization`.
  
  ==== event = 'ADD_MEMBER' OR 'REMOVE_MEMBER'
  
  The `ADD_MEMBER` and 'REMOVE_MEMBER' events for an `Organization` has a `data` attribute associated to a value that looks like this:
  
      {
          "organization" : "The organization ID",
          "members" : [{
              "id" : "The ID of the organization member",
              "role" : "The role of the member inside the organization (only when adding a member)"
          ]]
      }
  
  Those events when sent when a consumer is connected to an `Organization`.
  Only members of that `Organization` are sent.
  	
  *name*
  	
  A string corresponding to the `Organization` name. Defined only if value has changed.
  	
  *picture*
  
  A `base64` string corresponding to the `Organization` picture. Defined only if value has changed.
  	
  *members*
  
  An array defined only if members have changed and containing complex objects with two mandatory fields:
  
  * `id`: the `User` ID corresponding to the member.
  * `role`: the role of the member inside the `Organization`. Only defiened when the event is `ADD_MEMBER`.
  
  ==== event = 'ADD_VIEW' OR event = 'READ_VIEW'
  
  
negative.code: 
      {
          "unit" : "The time unit defining the group level of the time series",
          "category" : "The category id used to count artifacts"
          "preferences" : {
              "colors" : [{
              "label" : "The category label that should be displayed with a particular color",
  