fixed vertical dragging issue from hammer (which was found in network) in the timeline

lib/timeline/Core.js

@@ -115,6 +115,7 @@ Core.prototype._create = function (container) {
   // emitted via emitter
   this.hammer = new Hammer(this.dom.root);
   this.hammer.get('pinch').set({enable: true});
+  this.hammer.get('pan').set({threshold:5, direction:30}); // 30 is ALL_DIRECTIONS in hammer.
   this.listeners = {};
 
   var events = [

lib/timeline/component/CustomTime.js

@@ -82,6 +82,7 @@ CustomTime.prototype._create = function() {
   this.hammer.on('panstart', this._onDragStart.bind(this));
   this.hammer.on('panmove',  this._onDrag.bind(this));
   this.hammer.on('panend',   this._onDragEnd.bind(this));
+  this.hammer.get('pan').set({threshold:5, direction:30}); // 30 is ALL_DIRECTIONS in hammer.
   // TODO: cleanup
   //this.hammer.on('pan',   function (event) {
   //  event.preventDefault();

lib/timeline/component/ItemSet.js

@@ -198,6 +198,7 @@ ItemSet.prototype._create = function(){
   this.hammer.on('panstart', this._onDragStart.bind(this));
   this.hammer.on('panmove',  this._onDrag.bind(this));
   this.hammer.on('panend',   this._onDragEnd.bind(this));
+  this.hammer.get('pan').set({threshold:5, direction:30}); // 30 is ALL_DIRECTIONS in hammer.
 
   // single select (or unselect) when tapping an item
   this.hammer.on('tap',  this._onSelectItem.bind(this));