impossible to delete last or all host aliases

[hrez]

Hi,

While I can add or remove aliases in host record, it's impossible to remove all host record aliases using ObjectManager.UpdateHostRecord() by supplying aliases parameter as nil or []string{}

This is due to omitempty in
Aliases []string json:"aliases,omitempty" in HostRecord

It's true for both v1 and v2.

To test:

1. create host record with alias(es)
2. update host record to remove aliases
3. do GetHostRecord to observe aliases still present.