add `-h` and `--help`

[dennisangemi]

Documentation

Example code

# help message
if [[ $1 == "-h" || $1 == "--help" ]]; then
    # Visualizza la documentazione
    echo "frictionless2md - Convert frictionless datapackage to markdown"
    echo
    echo "Usage: frictionless2md [options]"
    echo
    echo "Options:"
    echo "  -h, --help      Get help (this message)"
    echo "  -w, --warnings  Show all warnings"
    echo "  -t, --tree      Print repository structure"
    echo "  -u, --user      Specify GitHub username and repository name"
    echo "  -o, --output    Specify output filename"
    echo ""
    echo "Example:"
    echo "frictionless2md -wt -u indecis-it/data -o my-project-metadata.md "

    exit 0
fi