[Feature] Add ability to sync inventory to Virtual Machine based hosts.

[q1x]

We would like to map NetBox fields to VM inventory as we can do with devices.
Steps that will need to be taken:

1. Move inventory logic out of the device module (move to tools?)
2. Change inventory_map to dev_inventory_map and vm_inventory_map in config.py
3. Make sure VM module calls set_inventory when configured
4. ....?
5. Profit!