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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 -->

)
    module = AnsibleAWSModule(argument_spec=argument_spec,
                              mutually_exclusive=[['subnets', 'subnet_mappings']])
    
    state = module.params.get("state")
    if state == 'present':
        if module.params.get("subnets") is None and module.params.get("subnet_mappings") is None:
            module.fail_json(msg="'subnets' or 'subnet_mappings' is required when state=present")
    if state is None:
        
        module.deprecate('State currently defaults to absent.  This is inconsistent with other modules'
                         ' and the default will be changed to `present` in Ansible 2.14',
                         version='2.14')
    
    listeners = module.params.get("listeners")
    if listeners is not None:
        for listener in listeners:
            for key in listener.keys():
                if key == 'Protocol' and listener[key] not in ['TCP', 'TLS']:
                    module.fail_json(msg="'Protocol' must be either 'TCP' or 'TLS'")
    connection = module.client('elbv2')
    connection_ec2 = module.client('ec2')
    elb = NetworkLoadBalancer(connection, connection_ec2, module)
    if state == 'present':
        create_or_update_elb(elb)
    else:
        delete_elb(elb)
if __name__ == '__main__':
    main()