Implement hypercore_vm_snapshot

[anazobec]

Closes #14

This MR implements the hypercore_vm_snapshot and other things needed for snapshot.

With resource hypercore_vm_snapshot, a user can create a USER type snapshot for a source VM by providing a VM UUID.

With resource hypercore_vm_snapshot_schedule, a user can create a schedule for automated snapshotting. The schedule can be applied to the created VM using the hypercore_vm reousrce with the added parameter: snapshot_schedule_uuid.

I also modified the VM data source, to also include data about the VMs' snapshot_schedule_uuid.

For more info, check the regenerated docs:

• hypercore_vm_snapshot
• hypercore_vm_snapshot_schedule
• hypercore_vm
• hypercore_vm data source

[justinc1]

Small changes suggested.

[justinc1]

We should extend hypercore_vm resource with snapshot_schedule_uuid attribute, and drop vm_uuid_list attribute from hypercore_vm_snapshot_schedule resource. This will make implementation much simpler - do you agree?

[justinc1]

Ty. Just some functions are unused, I suggest to remove them.

[justinc1]

TY and OK