Error getting alarms on Zabbix instances

[Ifat Afek]

In order to get alarms from zabbix on a specific resource, the user should specify the resource type and name in zabbix_conf.yaml file, for example:

zabbix:
- zabbix_host: host1
  type: nova.host
  name: host-0-1
- zabbix_host: instance1
  type: nova.instance
  name: first-instance

When Zabbix datasource tries to relate the alarm to the resource, it uses the name of the resource as its *id*. For hosts, the name and the id are the same, so it doesn't matter. For instances (or other types) it doesn't work, so instead of raising the alarm on an existing instance, a new instance is created.

Workaround: write the id of the instance in the 'name' parameter, like:

- zabbix_host: instance1
  type: nova.instance
  name: <first-instance-UUID>