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##### SUMMARY
<!--- Describe the new feature/improvement briefly below -->
Each VM instance in an Azure VM Scale Set (VMSS) has a computer name (hostname) which is distinct from the instance name. Currently azure_rm_virtualmachinescalesetinstance_facts returns the instance name but not the computer name. It would be extremely helpful if the module can return the computer name as well.

##### ISSUE TYPE
- Feature Idea

##### COMPONENT NAME
<!--- Write the short name of the module, plugin, task or feature below, use your best guess if unsure -->
azure_rm_virtualmachinescalesetinstance_facts

##### ADDITIONAL INFORMATION
<!--- Describe how the feature would be used, why it is needed and what it would solve -->
We are using this module in [Muchos](https://github.com/apache/fluo-muchos). If azure_rm_virtualmachinescalesetinstance_facts returned the computer name as well, it would help us populate etc/hosts and other related files much more seamlessly.
def __init__(self):
        
        self.module_arg_spec = dict(
            resource_group=dict(
                type='str',
                required=True
            ),
            vmss_name=dict(
                type='str',
                required=True
            ),
            instance_id=dict(
                type='str'
            ),
            tags=dict(
                type='list'
            )
        )
        
        self.results = dict(
            changed=False
        )
        self.mgmt_client = None
        self.resource_group = None
        self.vmss_name = None
        self.instance_id = None
        self.tags = None
        super(AzureRMVirtualMachineScaleSetVMInfo, self).__init__(self.module_arg_spec, supports_tags=False)
    def exec_module(self, **kwargs):