fix comment and fix pan animation

Author: fuzhenn

src/map/handler/Map.Drag.js

@@ -139,9 +139,8 @@ class MapDragHandler extends Handler {
             t = 5 * t;
             const dscale = isTouch ? 5 : 2.8;
             const targetPrjCoord = currentCenter.add(dxy._multi(dscale));
-            map._fixPrjOnWorldWide(targetPrjCoord);
-            const targetCoord = map.getProjection().unproject(targetPrjCoord);
-            map.panTo(targetCoord, { 'duration': isTouch ? t * 3 : t * 2, 'easing': 'outExpo' });
+            // map._fixPrjOnWorldWide(targetPrjCoord);
+            map._panTo(targetPrjCoord, { 'duration': isTouch ? t * 3 : t * 2, 'easing': 'outExpo' });
         } else {
             map.onMoveEnd(param);
         }

src/ui/UIMarker.js

@@ -10,6 +10,7 @@ import UIComponent from './UIComponent';
 
 /**
  * @property {Object} options - construct options
+ * @property {String} [options.containerClass=null]  - css class name applied to UIMarker's DOM container
  * @property {Boolean} [options.draggable=false]  - if the marker can be dragged.
  * @property {Number}  [options.single=false]     - if the marker is a global single one.
  * @property {String|HTMLElement}  options.content - content of the marker, can be a string type HTML code or a HTMLElement.