code: function restXhr(store, url, eventName, sortRequest) {
        // Set up request
        var xhr = new XMLHttpRequest();
        xhr.open("GET", url, true);
        // TODO - Set range header parameter
        xhr.setRequestHeader("Content-Type", "application/json");
        // Callback
        xhr.onload = function(e) {
          // If operation has been completed - ready state 4
          if (xhr.readyState === 4) {
            // Response status successfully completed - status 200
            if (xhr.status === 200) {
              // Set up store
              store._setUpData(xhr.response);
              // Process store data filters and lists
              vcomet.StoreMemory.processData(store);
              // Set data as sorted
              store.data.__sorted = sortRequest;
              // Update store data items length
              store.size = xhr.getResponseHeader("Total");
              // Trigger user callback once data has been retrieved
              vcomet.triggerCallback(eventName, store, store, [store.rootData]);
              vcomet.createCallback("onSourceChanged", store, store, [store.rootData]);
            }
          }
        };
        // Execute request
        store.onLoaded(function(){xhr.send()});
      }
docs: Set up and execute xhr request
  @param  {[type]} el      [description]
  @param  {[type]} url     [description]
  @param  {[type]} event   [description]
  @return {[type]}         [description]
   /*
  @function restXhr
  @description Set up and execute xhr request
  @param {Object} store [Store element]
  @param {String} url [Request url]
  @param {String} eventName [Callback event name]
  @param {Boolean} sortRequest [Whether or not data has been sorted]