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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 -->

protocol=dict(choices=['http', 'https', 'tcp', 'HTTP', 'HTTPS', 'TCP']),
            purge_tags=dict(default=True, type='bool'),
            stickiness_enabled=dict(type='bool'),
            stickiness_type=dict(default='lb_cookie'),
            stickiness_lb_cookie_duration=dict(type='int'),
            state=dict(required=True, choices=['present', 'absent']),
            successful_response_codes=dict(),
            tags=dict(default={}, type='dict'),
            target_type=dict(default='instance', choices=['instance', 'ip', 'lambda']),
            targets=dict(type='list'),
            unhealthy_threshold_count=dict(type='int'),
            vpc_id=dict(),
            wait_timeout=dict(type='int', default=200),
            wait=dict(type='bool', default=False)
        )
    )
    module = AnsibleAWSModule(argument_spec=argument_spec,
                              required_if=[
                                  ['target_type', 'instance', ['protocol', 'port', 'vpc_id']],
                                  ['target_type', 'ip', ['protocol', 'port', 'vpc_id']],
                              ]
                              )
    connection = module.client('elbv2')
    if module.params.get('state') == 'present':
        create_or_update_target_group(connection, module)
    else:
        delete_target_group(connection, module)
if __name__ == '__main__':
    main()