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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 -->

"Id": target['Id']
                                        }
                                    ]
                                )
                    except (botocore.exceptions.ClientError, botocore.exceptions.BotoCoreError) as e:
                        module.fail_json_aws(
                            e, msg="Couldn't register targets")
            else:
                if module.params.get("target_type") != "lambda":
                    current_instances = current_targets['TargetHealthDescriptions']
                    if current_instances:
                        instances_to_remove = []
                        for target in current_targets['TargetHealthDescriptions']:
                            instances_to_remove.append({'Id': target['Target']['Id'], 'Port': target['Target']['Port']})
                        changed = True
                        try:
                            connection.deregister_targets(TargetGroupArn=tg['TargetGroupArn'], Targets=instances_to_remove)
                        except (botocore.exceptions.ClientError, botocore.exceptions.BotoCoreError) as e:
                            module.fail_json_aws(e, msg="Couldn't remove targets")
                        if module.params.get("wait"):
                            status_achieved, registered_instances = wait_for_status(connection, module, tg['TargetGroupArn'], instances_to_remove, 'unused')
                            if not status_achieved:
                                module.fail_json(msg='Error waiting for target deregistration - please check the AWS console')
                
                else:
                    changed = False
                    if current_targets["TargetHealthDescriptions"]:
                        changed = True
                        
                        target_to_remove = current_targets["TargetHealthDescriptions"][0]["Target"]["Id"]