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##### SUMMARY
elb_network_lb and elb_target_group should support UDP, currently only HTTP, HTTPS and TCP are supported by ansible.

Based on the current pages, UDP and TCP_UDP are supported as protocols:
- https://docs.aws.amazon.com/elasticloadbalancing/latest/network/create-listener.html
- https://docs.aws.amazon.com/elasticloadbalancing/latest/network/create-target-group.html

##### ISSUE TYPE
- Feature Idea

##### COMPONENT NAME
- elb_target_group
- elb_network_lb

##### ADDITIONAL INFORMATION
It would be useful to use UDP as a protocol for an NLB, additionally, attached target groups would need to support UDP.

TCP_UDP is another protocol that it would be useful to add support for (a port that would take TCP or UDP traffic and not care)

<!--- Paste example playbooks or commands between quotes below -->
```yaml
    - name: Create logstash target group
      elb_target_group:
        name: logstash_bunyan_production_tg
        protocol: udp
        port: 5600
        vpc_id: "{{ vpc_facts.vpcs[0].id }}"
        state: present

    - name: Create nlb
      elb_network_lb:
        name: logstash_nlb
        subnets: "{{ private_subnets + public_subnets }}"
        health_check_path: "/"
        health_check_port: "9600"
        health_check_protocol: "http"
        protocol: "udp"
        port: "5600"
        listeners:
          - Protocol: UDP
            Port: 5600
            DefaultActions:
              - Type: forward
                TargetGroupName: logstash_bunyan_production_tg
        state: present
```

<!--- HINT: You can also paste gist.github.com links for larger files -->

}
                        ]
                    )
                    changed = True
                except (botocore.exceptions.ClientError, botocore.exceptions.BotoCoreError) as e:
                    module.fail_json_aws(
                        e, msg="Couldn't register targets")
    
    update_attributes = []
    
    current_tg_attributes = get_tg_attributes(connection, module, tg['TargetGroupArn'])
    if deregistration_delay_timeout is not None:
        if str(deregistration_delay_timeout) != current_tg_attributes['deregistration_delay_timeout_seconds']:
            update_attributes.append({'Key': 'deregistration_delay.timeout_seconds', 'Value': str(deregistration_delay_timeout)})
    if stickiness_enabled is not None:
        if stickiness_enabled and current_tg_attributes['stickiness_enabled'] != "true":
            update_attributes.append({'Key': 'stickiness.enabled', 'Value': 'true'})
    if stickiness_lb_cookie_duration is not None:
        if str(stickiness_lb_cookie_duration) != current_tg_attributes['stickiness_lb_cookie_duration_seconds']:
            update_attributes.append({'Key': 'stickiness.lb_cookie.duration_seconds', 'Value': str(stickiness_lb_cookie_duration)})
    if stickiness_type is not None and "stickiness_type" in current_tg_attributes:
        if stickiness_type != current_tg_attributes['stickiness_type']:
            update_attributes.append({'Key': 'stickiness.type', 'Value': stickiness_type})
    if update_attributes:
        try:
            connection.modify_target_group_attributes(TargetGroupArn=tg['TargetGroupArn'], Attributes=update_attributes)
            changed = True
        except (botocore.exceptions.ClientError, botocore.exceptions.BotoCoreError) as e:
            
            if new_target_group: