Added drag and drop feature to the task view

[asimbilal0001]

fixes #497

Files can now be directly dragged and dropped inside the main view to download them.

[monkeyWie]

Thanks for your PR, I have reviewed the code and I don't think using a global urlController is a good way to implement this.

Here's a suggestion that to listen to the url in the task_view and then redirect to the create_view with url parameter, if you're interested, u can update follow this way, thanks!

[asimbilal0001]

Thanks for the suggestion. I will update it that way asap