Docker-devbox-ddb

- Traefik: Use Jinja template for `ssl_config_template` parameter (Jinja context match the ddb.yml configuration).
- Traefik: Add `extra_services` in `traefik` feature. Extra service allow to configure a service running
outside of the docker stack inside traefik, so it's included in the docker network and still benefits of
docker-devbox features (domain name, SSL certificates, ...).
- Version: Make detached repo report the effective branch instead of `HEAD`.

- Config: Fix issues with custom config parameters.
- Shell: Raise an error when activate/deactivate was already called.

- Config: Fix overriding of default values with `DDB_OVERRIDE_*` environment variables.
- Core: Use `toilal/pyinstaller-linux` and `toilal/pyinstaller-windows` docker images to build binaries.

- Copy: Add `file:generated` events on copy to add copied files in `.gitignore`.
- Copy: Run copy feature on each `ddb configure` command instead of a single time.
- Shell: Use `.` instead of `source` to make `/bin/sh` work properly.
- Shell: Add `check-activated` command and avoid issues when activating the project many times.

- Jsonnet: Fix `duplicate field name` error when sharing a named volume on many docker-compose services.
- Certs: Add creation of `.signer.crt` to help automation of signer TLS Certificate configuration in the project.

- Shell: Fix binary shims when `-h`/`--help` is given as argument.
- Core: Add the `info` command which output compacted information about docker containers such as environment
variables, virtual host, exposed ports and binaries.
- Jsonnet: Fix `cache_from` value for docker services to match the `image` one
- Fixuid: Enhance fixuid configuration when image has no entrypoint defined.
- Config: Add support for `ddb.yml` configuration watch. If a project configuration file changes, configuration is
reloaded and command is runned again to update all generated files. It currently doesn't watch configuration files
from ~/.docker-devbox nor ~/.docker-devbox/ddb directories as it's based on `file` feature events.