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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 -->

subnets:
    description:
      - A list of the IDs of the subnets to attach to the load balancer. You can specify only one subnet per Availability Zone. You must specify subnets from
        at least two Availability Zones.
      - Required when I(state=present).
      - This parameter is mutually exclusive with I(subnet_mappings).
    type: list
  scheme:
    description:
      - Internet-facing or internal load balancer. An ELB scheme can not be modified after creation.
    default: internet-facing
    choices: [ 'internet-facing', 'internal' ]
    type: str
  state:
    description:
      - Create or destroy the load balancer.
      - The current default is C(absent).  However, this behavior is inconsistent with other modules
        and as such the default will change to C(present) in 2.14.
        To maintain the existing behavior explicitly set I(state=absent).
    choices: [ 'present', 'absent' ]
    type: str
  tags:
    description:
      - A dictionary of one or more tags to assign to the load balancer.
    type: dict
  wait:
    description:
      - Whether or not to wait for the network load balancer to reach the desired state.
    type: bool
  wait_timeout: