Store additional item fields as data- attributes

If additional item fields are defined on the DataSet or array being
passed to the timeline, store them as data- attributes on the content
element.

lib/timeline/component/item/ItemBox.js

@@ -132,6 +132,18 @@ ItemBox.prototype.redraw = function() {
     this.dirty = true;
   }
 
+  // set all other fields as data- attributes
+  var auxiliaryData = Object.keys(this.data);
+
+  for (var i in auxiliaryData) {
+    var c = auxiliaryData[i];
+    if (['start', 'end', 'content', 'title', 'id', 'className', 'group', 'type'].indexOf(c) < 0) {
+      dom.content.setAttribute('data-' + c, this.data[c]);
+    }
+  }
+
+
+
   // recalculate size
   if (this.dirty) {
     this.props.dot.height = dom.dot.offsetHeight;

lib/timeline/component/item/ItemPoint.js

@@ -121,6 +121,16 @@ ItemPoint.prototype.redraw = function() {
     this.dirty = true;
   }
 
+  // set all other fields as data- attributes
+  var auxiliaryData = Object.keys(this.data);
+
+  for (var i in auxiliaryData) {
+    var c = auxiliaryData[i];
+    if (['start', 'end', 'content', 'title', 'id', 'className', 'group', 'type'].indexOf(c) < 0) {
+      dom.content.setAttribute('data-' + c, this.data[c]);
+    }
+  }
+
   // recalculate size
   if (this.dirty) {
     this.width = dom.point.offsetWidth;

lib/timeline/component/item/ItemRange.js

@@ -115,6 +115,18 @@ ItemRange.prototype.redraw = function() {
     this.dirty = true;
   }
 
+
+  // set all other fields as data- attributes
+  var auxiliaryData = Object.keys(this.data);
+
+  for (var i in auxiliaryData) {
+    var c = auxiliaryData[i];
+    if (['start', 'end', 'content', 'title', 'id', 'className', 'group', 'type'].indexOf(c) < 0) {
+      dom.content.setAttribute('data-' + c, this.data[c]);
+    }
+  }
+
+
   // recalculate size
   if (this.dirty) {
     // determine from css whether this box has overflow