Using Object.keys on non object

[fabiancook]

I am experiencing an error when my response isn't an object ( or example if it were just a number )

Referring to the if statement here: https://github.com/swagger-api/swagger-js/blob/master/lib/http.js#L223

I would assume that the body will be null or undefined if it wasn't parseable by superagent, given this is the case we could just check for the value to exist, if it doesn't then try parse the original text as YAML