Support DTLS Setup

[jcrbsa]

Not is possible include digital certified file to realizade DTLS connection in CoAP messages

To development DTLS setup logic in client-side and to create new parameter to identify the operation when digital certified file is used.

For instance, it's necessary to investigate change points your source-code .

No additional context

[gerdemann]

Thank you for your message, jcrbsa.

Unfortunately node-coap does not support DTLS yet, so it cannot be implemented in this client.
There is an open issue in node-coap:
coapjs/node-coap#11

I close the issue until the support is available in node-coap.