Gantt Drag & Drop Tasks from an External Source

Hi, is it possible to drag & drop tasks from an external source instead adding a new task into the Gantt by + button?

Desired functionality:

Hello Marek,
Gantt doesn’t have a built-in method for that. We have it on our internal wishlist.
The dev team will think about adding it in the future.
Now, you need to implement a custom solution by using the Gantt API and Javascript.

I have the following examples that can help you to start:
http://snippet.dhtmlx.com/e01aa735e
http://snippet.dhtmlx.com/5/e219d14f0