Timestamp Microservice

User Stories:

1. The API endpoint is GET [project_url]/api/[date_string]
2. A date string is valid if can be successfully parsed.
   Note that the Unix timestamp needs to be an integer (not a string) specifying milliseconds.
   In our test we will use date strings compliant with ISO-8601 (for example: "2016-11-20") because this will ensure a UTC timestamp.
3. If the date string is empty the API uses the current timestamp.
4. If the date string is valid the API returns a JSON having the structure
   { "unix": (Unix timestamp), "utc": (UTC date and time) }
   for example: {"unix":1479663089000,"utc":"Sun, 20 Nov 2016 17:31:29 UTC"}
5. If the input date string is invalid the API returns a JSON having the structure
   { "error": "Invalid Date" }.
   It is what you get from the date manipulation functions.

Example Usage:

• GET /api/
• GET /api/2015-12-25
• GET /api/1451001600000
• GET /api/1451001600
• GET /api/invalid

Example Output:

{"unix":1451001600000,"utc":"Fri, 25 Dec 2015 00:00:00 UTC"}