Add controller container (ctl)

[reliveyy]

Goals:

1. Provide more sophisticated control over multiple docker-compose services. And also keep the built images generic (e.g. no curl and source to set aliases)
2. Build the foundation for a more complex and interactive CLI setup in the future

Features for the first version of ctl:

• check getinfo until synced to chain true and only then connect to simnet and open channel
• instead of setting aliases for xud, lnd etc in host system, instruct user to docker exec -it into ctl container which is connected to other containers and has alias already set
• status
  btcd / bitcoind (if container up + synced, then OK else check sync status and display "Syncing, 81%, if container down or other error, display "ERROR")
  ltcd / litecoind (if container up + synced, then OK else check sync status and display "Syncing, 81%, if container down or other error, display "ERROR")
  lndbtc (if container up + synced, then OK else check LND sync status and display "Syncing, 81%, if container down or other error, display "ERROR")
  lndltc (if container up + synced, then OK else check sync status and display "Syncing, 81%, if container down or other error, display "ERROR")
  xud (if container up + getinfo shows all normal = OK, else detailed error message)