Implement automated testing

[farlepet]

Create set of test cases to test functionality, likely utilizing coap-client to generate various sorts of requests.

[farlepet]

Preliminary set of test cases:

• Formatting
  • Plaintext
  • Base64
  • Hex
• Transports
  • UDP
  • TCP
  • DTLS
  • TLS
• Command execution
  • Stdin value
  • Variable replacement
    • COAPSERVER_PAYLOAD
    • COAPSERVER_RESOURCE
    • COAPSERVER_METHOD
  • Max execution time
• Request methods
  • PUT
  • POST
  • GET
    • Resource observation
• Resources
  • Static resources
  • Resource templates
  • Dynamic resources
• Log file creation
• Multi-block requests