Discussion around option flags

[dokun1]

The current node.js tool shows this when you type slackin without any options:

  Usage: slackin [options] <team-id> <api-token>

  Options:

    -c, --channels          One or more comma-separated channel names to allow single-channel guests [$SLACK_CHANNELS]
    -C, --coc               Full URL to a CoC that needs to be agreed to
    -x, --cors              Enable CORS for all routes
    -S, --css               Full URL to a custom CSS file to use on the main page
    -?, --help              Show the usage information
    -h, --hostname [value]  Hostname to listen on [$HOSTNAME or 0.0.0.0]
    -i, --interval <n>      How frequently (ms) to poll Slack [$SLACK_INTERVAL or 5000]
    -P, --path [value]      Path to serve slackin under
    -p, --port <n>          Port to listen on [$PORT or 3000]
    -s, --silent            Do not print out warns or errors
    -v, --version           Output the version number

Not only does the tool in swift need to output similar output, but we should decide which flags are relevant to this tool. I suspect all of them are valid and should be implemented, but I will not write those issues until some discussion here is made on the topic.