* Create a test matrix on Travis CI to help testing multiple options
* Change test_docker.sh to fail if any command in it fails
* Run black on the CI with --check option
* Fix formatting of project files using black
* Install black in the docker container
* Exclude migrations in black checks
* Fix Black formatting violations
* Run black on the whole generated project & fix issues
* Update generated project's .gitignore
* Post-gen gitignore .env/ and .env
* Fix linesep between gitignored entries
* Persist `.env/**/*` files into cookiecutter-django's VCS
* Rename .env/ to .envs/
* Reference the newly created .envs/**/.* files in local.yml
* Reference the newly created .envs/**/.* files in production.yml
* Delete .env.example
* Refactor post-gen-project.py
Closes#1299.
* Implement production-dotenv-files-to-dotenv-file merge script
* Create shared PyCharm Run Configuration for the automation script
* Randomize POSTGRES_PASSWORD in ./envs/(.local|.production)/.postgres
* Default POSTGRES_PASSWORD and POSTGRES_USER to random values
* Fix jinja linebreaks in local.yml
* Spaces in production.yml
* Fix post-merge leftovers & set DJANGO_ADMIN_URL automatically
* Prettify here and there
* Fix FileNotFoundError
* Leave a TODO in post_gen_hook.py
* Introduce keep_local_envs_in_vcs option
* Remove envs when not opted for
* Inline pre_gen_project.py if-condition
* Get rid of PROJECT_DIR_PATH in post_gen_project.py
* Clean up the docs
* Match copyright notices
* Document envs ins and outs
* Fix ./hooks/pre_gen_project.py asking user to select an option once only
+ prettify output
* Fix pre_gen hook not really exiting when it should
* Refactor & prettify ./hooks/post_gen_project.py
* Ensure same POSTGRES_USER is set across environments
+ get rid of env.example in favor of pre-generated .env.
