Launch a topology view from a device

[jmanteau]

On larger site with a lot of devices, the topology is not useful.

An alternative could be to allow to launch from a device but with a hop count of 1 to see only the neighbors.

Then on the topology view, we could extend the number of hop count to be visualized based on the user input. This could allow a better topology view for a set of devices inside a site.

[dreng]

This seems to be not easy to implement. Another solution might be #57 and my pull request #58. With the current version of Netbox you should use Locations in order to group and nest organizational units.