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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 -->

returned: when state present
    type: int
    sample: 5
healthy_threshold_count:
    description: The number of consecutive health checks successes required before considering an unhealthy target healthy.
    returned: when state present
    type: int
    sample: 5
load_balancer_arns:
    description: The Amazon Resource Names (ARN) of the load balancers that route traffic to this target group.
    returned: when state present
    type: list
    sample: []
matcher:
    description: The HTTP codes to use when checking for a successful response from a target.
    returned: when state present
    type: dict
    sample: {
        "http_code": "200"
    }
port:
    description: The port on which the targets are listening.
    returned: when state present
    type: int
    sample: 80
protocol:
    description: The protocol to use for routing traffic to the targets.
    returned: when state present
    type: str
    sample: HTTP