Well for now you can look at this thread where I was asking for pretty much the same thing.
If you can wait a bit I am going to release the two combined libs in addition to header/json parsing. Right now I can successfully make a request to httpbin and get a value from the json. I ended up using the jsmn/json_arduino lib since I feel that the other library is pretty bloated. Because of this, I am not sure if the json parser can parse complex objects.
I am not sure about the ETA on this combined library as I only get a few hours a day to work on it but I think that I should have something to show by the end of the weekend.