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##### SUMMARY
<!--- Describe the new feature/improvement briefly below -->
Add support for `MaxInstanceLifetime` option to AWS ec2_asg module.
AWS feature introduction link: https://aws.amazon.com/about-aws/whats-new/2019/11/amazon-ec2-auto-scaling-supports-max-instance-lifetime/

##### ISSUE TYPE
- Feature Idea

##### COMPONENT NAME
<!--- Write the short name of the module, plugin, task or feature below, use your best guess if unsure -->
ec2_asg

##### ADDITIONAL INFORMATION
<!--- Describe how the feature would be used, why it is needed and what it would solve -->
Usage example:
<!--- Paste example playbooks or commands between quotes below -->
```yaml
- ec2_asg:
    name: myasg
    region: us-east-1
    launch_config_name: my_new_lc
    min_size: 1
    max_size: 5
    desired_capacity: 3
    max_instance_lifetime: 604800  # seconds
```

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raw_mixed_instance_object = autoscaling_group.get('MixedInstancesPolicy')
    if raw_mixed_instance_object:
        properties['mixed_instances_policy'] = [x['InstanceType'] for x in raw_mixed_instance_object.get('LaunchTemplate').get('Overrides')]
    metrics = autoscaling_group.get('EnabledMetrics')
    if metrics:
        metrics.sort(key=lambda x: x["Metric"])
    properties['metrics_collection'] = metrics
    if properties['target_group_arns']:
        region, ec2_url, aws_connect_params = get_aws_connection_info(module, boto3=True)
        elbv2_connection = boto3_conn(module,
                                      conn_type='client',
                                      resource='elbv2',
                                      region=region,
                                      endpoint=ec2_url,
                                      **aws_connect_params)
        tg_paginator = elbv2_connection.get_paginator('describe_target_groups')
        tg_result = tg_paginator.paginate(TargetGroupArns=properties['target_group_arns']).build_full_result()
        target_groups = tg_result['TargetGroups']
    else:
        target_groups = []
    properties['target_group_names'] = [tg['TargetGroupName'] for tg in target_groups]
    return properties
def get_launch_object(connection, ec2_connection):
    launch_object = dict()
    launch_config_name = module.params.get('launch_config_name')
    launch_template = module.params.get('launch_template')
    mixed_instances_policy = module.params.get('mixed_instances_policy')
    if launch_config_name is None and launch_template is None:
        return launch_object
    elif launch_config_name: