message: Fixed getInstallLink() error
  controller.getInstallLink() should be adapter.getInstallLink()
diff: @@ -103,7 +103,7 @@ const adapter = new SlackAdapter({
  // Create a route for the install link.
  // This will redirect the user to Slack's permission request page.
  controller.webserver.get('/install', (req, res) => {
  - res.redirect(controller.getInstallLink());
  + res.redirect(adapter.getInstallLink());
  });
  // Create a route to capture the results of the oauth flow.
  