Wait for url to be ready with progress bar

[larencozart]

• Added a waitForAppToBeReady file
• This file polls our url, and waits for a 200 response, displaying a progress bar while the user waits

To test this:

1. Just in case, delete your node_modules
2. Run npm install
3. Run npm run build
4. Run node dist/cli/cli.js destroy
5. Run node dist/cli/cli.js deploy

[jq-ln]

Progress bar is duplicated when screen is re-sized, but that can be figured out later. Otherwise, everything works well!