http-builder-0.7.x
groovy.codehaus.org/modules/http-builder/
https://github.com/jgritman/httpbuilder
https://github.com/jgritman/httpbuilder/tree/master/src/main/java/groovyx/net/http

http-client-4.5.1
http-core-4.4.3

http://stackoverflow.com/questions/28843915/how-to-get-complete-response-for-groovy-restclient-failed-response

restClient = new RESTClient("http://${Server}")
restClient.handler.failure = { resp, data ->
...
    throw new HttpResponseException(resp.getStatus(),
        "HTTP call failed. Status code: ${resp.getStatus()}\n${headers}\n" +
        "Response: " + (resp as HttpResponseDecorator).getData())
    return resp
}