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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 -->

if elb_obj.elb:
        elb_obj.delete()
    elb_obj.module.exit_json(changed=elb_obj.changed)
def main():
    argument_spec = (
        dict(
            cross_zone_load_balancing=dict(type='bool'),
            deletion_protection=dict(type='bool'),
            listeners=dict(type='list',
                           elements='dict',
                           options=dict(
                               Protocol=dict(type='str', required=True),
                               Port=dict(type='int', required=True),
                               SslPolicy=dict(type='str'),
                               Certificates=dict(type='list'),
                               DefaultActions=dict(type='list', required=True)
                           )
                           ),
            name=dict(required=True, type='str'),
            purge_listeners=dict(default=True, type='bool'),
            purge_tags=dict(default=True, type='bool'),
            subnets=dict(type='list'),
            subnet_mappings=dict(type='list'),
            scheme=dict(default='internet-facing', choices=['internet-facing', 'internal']),
            state=dict(choices=['present', 'absent'], type='str'),
            tags=dict(type='dict'),
            wait_timeout=dict(type='int'),
            wait=dict(type='bool')
        )