* mail binary
* initial work
* make env vars available
* typo
* some fixes
* make script ugly, to satisfy linter..
* mailserver.env updated
* Version to welcome message added
* remove VERSION file references
* VERSION --> DMS_VERSION
* fetch remote version
* variable usage
* Quoting added
* edge test & docu
* dash removed
* subject changed
* re-add VERSION
* VERSION added
* new file: VERSION
* rewrite
* unnecessary additions from fail2ban PR removed
* UPDATE_CHECK_INTERVAL added
* syntax check & _log function
* comment added
* final commit
* splitting start-mailserver.sh
* refactoring part 2
* refactored setup-stack.sh
* stzarted adjusting target/bin/*.sh to use new usage format
* corrected lowercase-uppercase test error
* better handling of .bashrc variable export
* linting tests and fix for default assignements
* last stylistic changes and rebase