Description:

Generates a new cable channel for the server (in Ruby) and client (in JavaScript).
Pass the channel name, either CamelCased or under_scored, and an optional list of channel actions as arguments.

Examples:

`bin/rails generate channel notification`

creates a notification channel class, test and JavaScript asset:
    Channel:    app/channels/notification_channel.rb
    Test:       test/channels/notification_channel_test.rb
    Assets:     $JAVASCRIPT_PATH/channels/notification_channel.js

`bin/rails generate channel chat speak`

creates a chat channel with a speak action.

`bin/rails generate channel comments --no-assets`

creates a comments channel without JavaScript assets.