Add features, and clean up code

* Added a ‘debug’ mode for the entrypoint script.
* Changed some database environment variables to ‘required’.
* Added some more database environment variables.
* Structured and cleaned up the entry point script.
Update README.md
Fix typos
Fix CMD
Release v1.1

* Added debug and verbose options for dovecot.
* Made some db environment variables required.
* Added a debug run mode.
* Updated README.md with full instructions.
* Cleaned up entrypoint script.
Merge branch 'release-1.1'