This script creates a directory `backend/package` which only contains the
files required by the backend at runtime:
- The contents of `dist`
- `node_modules` minus `typescript` and `@typescript-eslint`.
These packages are build-only and are larger than the remaining whole package.
By using only `backend/package` in the Docker image,
the backend content size in the image is decreased by 70% to 31M.
This, along with the improved copying in the Dockerfile, reduces the
backend image size by 44% to 200M.
(Step `RUN chown -R 1000:1000 /backend ...` created a layer that effectively
duplicated the backend.)
* Recreate a docker dir with all docker files inside and add init.sh
* Add docker/README.md with example docker-compose.xml
* Add mysql vars for mempool-config.json
* Port can be set from env var in docker-compose.xml
* Update docker-compose.xml example to use latest tag
* Remove armv7 architecture from build workflow
* Remove master git-hash file
* Remove useless ':' in sed
