Description

When parameters are missing (alias destination in that case), this error is shown:

./setup.sh alias add postmaster@office
/usr/local/bin/setup: line 119: 2: unbound variable

--- UNCHECKED ERROR
  - script    = ./setup.sh
  - function  = _main
  - command   = ${CRI} exec "${USE_TTY}" "${CONTAINER_NAME}" setup "${@}"
  - line      = 229
  - exit code = 1

This should not have happened. Please file a bug report.

This PR solves that, by showing the usage instead.

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Improvement (non-breaking change that does improve existing functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation (README.md or the documentation under docs/)
• If necessary I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes