Use TreeGrid renderer and keys

treegrid.js

@@ -1,7 +1,7 @@
 /**
  * Very simple and fast tree grid/table, compatible with dynamic loading and jQuery fixedHeaderTable
  * License: MPL 2.0+, (c) Vitaliy Filippov 2016+
- * Version: 2016-06-05
+ * Version: 2016-06-06
  */
 
 /**
@@ -114,8 +114,7 @@ TreeGrid.prototype._setProps = function(el, props)
         el.innerHTML = props;
     else
         for (var j in this.bindProps)
-            if (props[j])
-                el[j] = props[j];
+            el[j] = props[j] || '';
 }
 
 // Simple cell editing
@@ -385,6 +384,11 @@ function TreeGridNode(node, grid, level, insertBefore, startHidden)
     }
 }
 
+TreeGridNode.prototype.getKey = function()
+{
+    return this.key;
+}
+
 TreeGridNode.prototype.getChildByKey = function(key)
 {
     return this.childrenByKey[key];