IPAM Service model improvements

[renatoalmeidaoliveira]

The actual version of Service model, is limited to one service per device or virtual machine, I think it would be better if the service models have one more attribute for version, and uses Many to Many relationships.
That way if my devices uses OpenSSH for SSH port 22, I doesn't need to create a service for each device that uses SSH/22, and with the version attribute it's possible to integrate with CVE e open exploits bases