Identify command that triggered callback

[JamesBrill]

To enable consumers that provide an array of command phrases for the same command callback, the lib now passes in the matched command phrase back to the callback. This is passed in through the last argument as the command property. Example:

    {
      command: ['Hello', 'Hi'],
      callback: ({ command }) => setMessage(`Hi there! You said: "${command}"`),
      matchInterim: true
    }