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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 params['TargetType'] == 'ip':
            fail_if_ip_target_type_not_supported(module)
    
    tg = get_target_group(connection, module)
    if tg:
        diffs = [param for param in ('Port', 'Protocol', 'VpcId')
                 if tg.get(param) != params.get(param)]
        if diffs:
            module.fail_json(msg="Cannot modify %s parameter(s) for a target group" %
                             ", ".join(diffs))
        
        health_check_params = dict()
        
        if health_options:
            
            if 'HealthCheckProtocol' in params and tg['HealthCheckProtocol'] != params['HealthCheckProtocol']:
                health_check_params['HealthCheckProtocol'] = params['HealthCheckProtocol']
            
            if 'HealthCheckPort' in params and tg['HealthCheckPort'] != params['HealthCheckPort']:
                health_check_params['HealthCheckPort'] = params['HealthCheckPort']
            
            if 'HealthCheckIntervalSeconds' in params and tg['HealthCheckIntervalSeconds'] != params['HealthCheckIntervalSeconds']:
                health_check_params['HealthCheckIntervalSeconds'] = params['HealthCheckIntervalSeconds']
            
            if 'HealthCheckTimeoutSeconds' in params and tg['HealthCheckTimeoutSeconds'] != params['HealthCheckTimeoutSeconds']:
                health_check_params['HealthCheckTimeoutSeconds'] = params['HealthCheckTimeoutSeconds']
            
            if 'HealthyThresholdCount' in params and tg['HealthyThresholdCount'] != params['HealthyThresholdCount']:
                health_check_params['HealthyThresholdCount'] = params['HealthyThresholdCount']