aio-talk should support eturnal's tls transport

[rseabra]

Steps to reproduce

1. the lack of TLS support in aio-talk should be viewed as a security vulnerability

Expected behavior

1. TLS should be supported

Actual behavior

1. no TLS is supported

Other information

/conf $ cat eturnal.yml 
eturnal:
  listen:
    - ip: "::"
      port: 3478
      transport: udp
    - ip: "::"
      port: 3478
      transport: tcp
  log_dir: stdout
  log_level: warning

eturnal supports tls endpoint, there is a (commented out) example at https://github.com/processone/eturnal/blob/1.12.2/config/eturnal.yml

    #-
    #  ip: "::"
    #  port: 5349
    #  transport: tls

  ## TLS certificate/key files (must be readable by 'eturnal' user!):
  #tls_crt_file: /etc/eturnal/tls/crt.pem
  #tls_key_file: /etc/eturnal/tls/key.pem

[rseabra]

I'm not sure how easy it will be for me to build an aio-talk container, but I'll try to do that in order to propose appropriate patches. It will require quite some refactoring of start.sh as the way it "templates" eturnal.yml doesn't allow for optional features.

I've forked into https://github.com/rseabra/all-in-one where I'll do some work.

[rseabra]

Already started some work at https://github.com/rseabra/all-in-one/tree/tls/Containers/talk

[rseabra]

I created #7599 to fix this issue.