Various zabbix.host_present inventory fixes
Various zabbix.host_present inventory fixes

- Adds inventory_clean parameter to select if the current inventory
  should or not be overwrited
- Allows inventory to be passed as a list or dictionary
- Don't remove the current inventory if inventory parameter is missing
- Compare the key values and not only the keys itself to update inventory
- Update documentation with the new parameter and dictionary change

saltstack/salt,saltstack/salt,saltstack/salt,saltstack/salt,saltstack/salt