Add `$DC_BIND` to change service bindings
Add `$DC_BIND` to change service bindings

Can assign a per-project default bind address for mappings. Setting
`DC_BIND=10.20.30.1` in `.env` next to the `docker-compose.yml` would
only listen on that address, allowing, e.g., two projects to have a
`redis` service with `ports: ["6379:6379"]`.

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