Keep JSON minified in all responses

Extra whitespace adds needless response size to requests, and many clients for human consumption will automatically "prettify" JSON output. It is best to keep JSON responses minified e.g.:

{"beta":false,"email":"[email protected]","id":"01234567-89ab-cdef-0123-456789abcdef","last_login":"2012-01-01T12:00:00Z","created_at":"2012-01-01T12:00:00Z","updated_at":"2012-01-01T12:00:00Z"}

Instead of e.g.:

{
  "beta": false,
  "email": "[email protected]",
  "id": "01234567-89ab-cdef-0123-456789abcdef",
  "last_login": "2012-01-01T12:00:00Z",
  "created_at": "2012-01-01T12:00:00Z",
  "updated_at": "2012-01-01T12:00:00Z"
}

You may consider optionally providing a way for clients to retrieve more verbose response, either via a query parameter (e.g. ?pretty=true) or via an Accept header param (e.g. Accept: application/vnd.heroku+json; version=3; indent=4;).