code: function(callback) {
              callback = callback || function() {};
              
              var that = this;
              var req = this.post("control", {action: "enablepreview"}, function(err) {
                  callback(err, that);
              });
              
              return req;
          }
docs: Enables preview generation for a search job.
  
  @example
  
  var job = service.jobs().item("mysid");
  job.disablePreview(function(err, job) {
  console.log("PREVIEW ENABLED");
  });
  
  @param {Function} callback A function to call with this search job: `(err, job)`.
  
  @endpoint search/jobs/{search_id}/control
  @method splunkjs.Service.Job