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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 -->

listeners_obj.changed = True
    
    for listener_to_add in listeners_to_add:
        listener_obj = ELBListener(elb_obj.connection, elb_obj.module, listener_to_add, elb_obj.elb['LoadBalancerArn'])
        listener_obj.add()
        listeners_obj.changed = True
    
    for listener_to_modify in listeners_to_modify:
        listener_obj = ELBListener(elb_obj.connection, elb_obj.module, listener_to_modify, elb_obj.elb['LoadBalancerArn'])
        listener_obj.modify()
        listeners_obj.changed = True
    
    if listeners_obj.changed:
        elb_obj.changed = True
    
    elb_obj.update()
    
    listeners_obj.update()
    
    elb_obj.update_elb_attributes()
    
    snaked_elb = camel_dict_to_snake_dict(elb_obj.elb)
    snaked_elb.update(camel_dict_to_snake_dict(elb_obj.elb_attributes))
    snaked_elb['listeners'] = []
    for listener in listeners_obj.current_listeners:
        snaked_elb['listeners'].append(camel_dict_to_snake_dict(listener))
    
    snaked_elb['tags'] = boto3_tag_list_to_ansible_dict(snaked_elb['tags'])
    elb_obj.module.exit_json(changed=elb_obj.changed, **snaked_elb)
def delete_elb(elb_obj):