orgchart 4.0.0

on Node.js NPM

In order to make enough space fro users to build up their remote datasource, we make the following changes in this version:

1. remove the option "ajaxURL"
2. remove the events "load-[relation].orgchart"
3. add new method "addAncestors(data, parentId)"
4. add new method "addDescendants(data, $parent)"