message: Update Readme with comments
diff: @@ -68,6 +68,7 @@ const options = {
  };
  const graphScopes = ["user.read", "mail.send"]; // An array of graph scopes
  +// Initialize the MSAL @see https://github.com/AzureAD/microsoft-authentication-library-for-js/wiki/MSAL-basics#initialization-of-msal
  const userAgentApplication = new Msal.UserAgentApplication(clientId, undefined, callback, options);
  const authProvider = new MicrosoftGraph.MSALAuthenticationProvider(userAgentApplication, graphScopes);
  ```
  