API Project: Request Header Parser Microservice

User Stories:

1. The API endpoint is [PROJECT_URL]/api/whoami
2. I can get the IP address, preferred languages (from header Accept-Language)
   and system infos (from header User-Agent) for my device.

Example Usage:

https://stax-request-headerparser.glitch.me/api/whoami

Example Output:

{
"ipaddress": "159.20.14.100",
"language": "en-US,en;q=0.5",
"software": "Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:50.0) Gecko/20100101 Firefox/50.0"
}