API Project: URL Shortener - php5

User Stories:

1. I can POST a URL and I will receive a shortened URL in the JSON response.
2. If I pass an invalid URL that doesn't follow the valid http://www.example.com format, the JSON response will contain an error instead.
3. When I visit that shortened URL, it will redirect me to my original link..

Creation:

URL to shorten:

Example output:

{ "original_url": "https://www.google.com", "short_url": "1" }

Usage:

http://emant.altervista.org/micro/api/shurl/1 redirects to https://www.google.com