Netbox plugin: make syncing OS configurable

[peterbaumert]

Is your feature request related to a problem? Please describe.
Currently when syncing to netbox the Operating System is always written to the Platform field.
Yet this "only" uses debian/windows etc as platform. In my environment I need to differentiate between OS versions.

Describe the solution you'd like
I would either like to completely turn OS sync on/off or make it configurable that its only synced when its empty in netbox.

Describe alternatives you've considered
Not sure there is a feasible other solution.

Additional context
Maybe this could be a general approach, also for Interfaces and so on, there I face similar issues as well. As virtual interfaces e.g. are not shown in Xen Orchestra, hence the sync always deletes them.

[pdonias]

This is indeed a more general problem that we've discussed in the past but we haven't found an easy solution so far, unfortunately. XO is assumed to be a source of truth and overwrites anything that hasn't the correct value. We changed a few things before to avoid as much as possible deleting information that was added manually, but the question remains for many other fields that are synchronized by XO.

I don't think turning OS sync on/off would be a solution as we'd need to do that for all the fields and it kills the concept of synchronization.

We also discussed adding the OS version here but it wouldn't really work because of information inconsistencies.