move instance from one network to another by draging network connection of instance

Summary
=======

To provide the support for editing/change network connections between instance and Network by simply draging the connectivity of an instance from one network to another.

Motivation
========

Currently to move an instance from one network to another there is 2 to 3 steps to follow and to move multiple instance user have to view the Network topology page several times. Because the Horizon "Network topology" page is not interactive for modifications.

Description
=========

- A new feature will be added which will allow the tenant to move instance from one network to another network by draging the connection.