Hammer CLI

Description

Recently, image-id removed from compute-attributes while creating host and instead now user needs to pass --image-id option while creating a host.
However host creation fails when user selects hostgroup.

How Reproducible:
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Always

Steps:
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hammer host create --name gceHammered3 --organization-id 1 --location-id 2 --hostgroup-id 1 --provision-method 'image' --volume 'size_gb=13' --managed true --compute-attributes 'machine_type=g1-small,network=default,associate_external_ip=true' --image-id 1
Could not create the host:
  Missing arguments for 'id'

Actual Behaviour:
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Host create command gives a failure for 'id'.

Expected Behaviour:
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1. The host should be provisioned

Note that when I try to send "image-id" key-value inside --compute-attributes and removed --image-id option, I am able to provision a host.