API Basejump: Timestamp microservice

User stories:

1. I can pass a string as a parameter, and it will check to see whether that string contains either a unix timestamp or a natural language date (example: January 1, 2016)
2. If it does, it returns both the Unix timestamp and the natural language form of that date.
3. If it does not contain a date or Unix timestamp, it returns null for those properties.

Example usage:

https://timestamp-microservice-cs.herokuapp.com/December%2015,%202015

https://timestamp-microservice-cs.herokuapp.com/1450137600

Example output:

{
  "unix": 1450137600,
  "natural": "December 15, 2015"
}