docker-compose.yml improvements

[sumitsrana]

It would be nice if you allowed docker-compose.yml to pick up values from a locally defined .env file.

For example, ~/.nanobot is right now hardcoded in the volumes section.
It would be nice if it could be defined via a variable (such as DOT_NANOBOT_PATH) in a .env file. Then the volumes section in docker-compose.yml could be changed to:

  volumes:
    - ${DOT_NANOBOT_PATH:-~/.nanobot}:/root/.nanobot

I also modified my docker-compose.yml to pass in localtime and timezone.

  volumes:
    - ${DOT_NANOBOT_PATH:-~/.nanobot}:/root/.nanobot
    - /etc/localtime:/etc/localtime:ro
    - /etc/timezone:/etc/timezone:ro